Please have pity on 49ers fans

Internet comment sections are a fascinating culture, in the science class sense. Introduce a stimulus, and watch the ideas and emotion grow and branch like hungry germs, ending only when everything has been consumed. Eventually, even the trolls run out of fuel, but what they leave in their wake can reveal the temperature of a fanbase. Let's use Niners Nation as an example.

The 49ers have had an awful offseason. It began with a "mutual" parting of ways with Jim Harbaugh, after an 8-8 season, that probably wasn't mutual. The same front office that seemingly chased away a successful head coach hired Jim Tomsula, a long-time defensive line coach with no head coaching experience outside of a one-game interim stint in 2010 and one season leading the Rhein Fire before NFL Europe bellied up.

Then came the onslaught of personnel losses. Frank Gore left for the Colts and Mike Iupati left for the Cardinals. Numerous free agents are still flapping in the wind. Rumors persist, crazy as they are, that the 49ers are shopping quarterback Colin Kaepernick for a trade.

But the final straws, the thing that sent Niners fans into a tailspin down into a mire of pity and self-loathing, were reports released Monday nearly within minutes of each other that two defensive greats -- defensive end Justin Smith and linebacker Patrick Willis -- were set to retire. This is what this offseason has felt like in San Francisco:

There was one saving grace of Willis' retirement, a second-year linebacker named Chris Borland who racked up 107 tackles and two interceptions in 11 appearances and eight starts when injuries pressed him into action. Then someone somewhere uttered "it could be worse" and this happened:

49ers fans don't have much to be sad about in the grand scheme. They have plenty of Super Bowl titles, and heading into last season had gone to three straight NFC Championship games with a Super Bowl appearance in 2012. That's pretty good! And a much happier predicament than, say, the recent history of the Buccaneers (to choose one).

But 49ers fans are sad, and understandably so. Let's take a look at the factors feeding the pathos.

Reason 1) Jim Tomsula probably isn't ready to be an NFL head coach

Let's preface this next bit by pointing out that Tomsula has had an immensely successful career by any standard. He has earned his way up from the high school ranks, through small colleges and a long stay in Europe before landing as the 49ers' defensive line coach in 2007. Since, the 49ers' defensive front has been one of the best in the league. In Tomsula's first year, the team went from allowing 4.1 yards per carry -- tied for 14th in the league -- to 3.8 yards per carry -- fifth. The 49ers had not given more than 3.9 yards per carry until this past season when that average climbed to 4.0, yet the team still ranked seventh in the NFL giving up 100.8 yards rushing per game.

Individual defensive linemen under Tomsula have been outstanding. Aaron Lynch, Aldon Smith and Ray McDonald have been hits (not taking into account the off-field problems of the latter two), and Ian Williams has become a starting role after being signed as an undrafted rookie free agent in 2011. Smith went to five straight Pro Bowls after spending seven Pro Bowl-less seasons in Cincinnati. One could make the argument that Tomsula is one of the finest defensive line coaches in the NFL, which means he's one of the best among the thousands employed worldwide.

That's awesome. Tomsula is clearly a skilled and competent man much loved by his players.

But 49ers fans may rightfully be scared by the fact that Tomsula has never even been a coordinator at the NFL level, much less a head coach. His introductory press conference was disconcerting. Nevermind Tomsula's poor public speaking skills, more worrisome was the fact that he was unable to articulate a schematic philosophy.

Tomsula is clearly a great teacher -- plenty of players have indicated as much -- but early signs suggest he may struggle switching from a micro- to a macro-managing role. At the very least, we don't know, and that's worrisome.

Reason 2) Eras are ending

How do you gather the energy to reinvest in something that is the same in name only?

The 49ers are still the "49ers", but the team will be vastly different from recent iterations. The men who are leaving were not only successful, but had been around long enough to be considered essential. Harbaugh, Gore, Willis, Smith and Iupati had spent a combined 34 seasons in San Francisco. Willis, Smith and Gore had been captains. The 49ers still have punter Andy Lee (12 years with the team), tight end Vernon Davis (nine years) and left tackle Joe Staley (eight years), but it's understandable to feel that an era has passed.

Fans first know players as men who wear the jersey they root for. Then they get to know the men themselves. When those men move on, coping isn't as easy as just rooting for the new guys in their place. Things will never be as they once were, and even if that meant that things were getting better, it's still a sad thought.

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Reason 3) We're six months away from the season opener

The worst part about the 49ers' situation is that the hits are coming now. The conversation of the last week will be the conversation until September. The events were so great that they subsume anything else.

The 49ers aren't a sad team because they're expected to be bad. They're sad because the light of hope has already been extinguished. The Jaguars, for example, probably won't contend a championship next season, but they have a ton of cap space, and a shiny new Julius Thomas, and second-year Blake Bortles, and a sense of excitement about their potential growth.

The 49ers look like the same team that regressed last season, less a few Hall of Fame-caliber player. If the season opener were just around the corner, then these gut punches could be galvanizing. They'd be a rally point, and the Tomsula era might start with 49ers as underdogs, something befitting an unassuming, hands-on coach.

That might still happen, but some of the energy will have worn off by then, and in the mean time fans are wearing the weight of the departures as they trudge through the offseason.

Reason 4) There is now reason to wonder whether fandom is worth the effort

This reason probably applies to a lot of football fans right now. Borland's retirement continued a trend of good football players retiring with something left in the tank -- Jake Locker, Jason Worilds, Maurice Jones-Drew and, of course, Willis all hung up their careers this offseason -- and it may not be a coincidence that they mostly played high-contact positions.

Evidence suggests that the pool of available players will shrink in the coming years -- see: the declining participation in youth football. No, the NFL probably isn't folding any time soon, but increasingly players may decide that suffering potential long-term head trauma isn't worth playing a lucrative sport. Then the same question befalls fans: Is it worth cheering knowing that players are getting hurt in unseen ways?

49ers fans may suffer more because one of their own made the most damning indictment against football. Borland was just 24, held a promising future and fit the great football myth of the too-small, too-slow athlete who succeeds by sheer toughness and tenacity. Those guys aren't supposed to quit until their bodies fall apart. The fact that Borland left the game should send all fans into an existential crisis.

That ever-present concern won't help 49ers fans get excited for the upcoming season. At this moment, the immediate future is admittedly bleak. It's an awful feeling, but it only feels so bad because so recently the 49ers were considered among the NFL elite. There should be solace in that for Niners fans. Embrace it, because things may not get better for a long time.

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