From what I can discern, there are two primary reasons that chasers (from veterans and newcomers alike) choose to use social media over Stormtrack.
1.) Audience and reach. Even in Stormtrack's heydey in the 2000s, posting a good photo would result in it being seen by maybe 2,000 people total, mostly within the chasing community. The best-case scenario was when a major media outlet or site like Digg or Fark would link to a thread and send 50,000-80,000 visitors here. Contrast that with social media, where the audience goes well beyond the weather community, can easily reach the millions and be seen by pretty much every figure in the weather world including the NWS and local/national TV celebrities including Jim Cantore, James Spann and the like.
My thoughts: No one likes taking the time to post something, then get no views or feedback on it. Talking to yourself gets tiring very fast for most people. Unfortunately, that's become the norm here. But it's a feedback loop: many avoid ST due to the inactivity, but the inactivity comes from everyone like them avoiding it!
2.) Today's mainstream storm chasing culture is at odds with most of ST's core long-timers. I see this as Stormtrack's biggest challenge. Let's face it, the vast majority of new chasers who started after 2008 were inspired not by the likes of Hoadley, Marshall, Doswell or Bluestien. Not by the NOVA special or even Twister. No, their icon is Reed Timmer. He's their introduction into the chasing hobby. They imitate him, look up to him and want to live his adventures. Chasing since 2008 has basically been Timmer's world. The rest of us are outside of it and left behind. And most of us old timers, understandably, simply loathe everything about that, won't tolerate any of it and are openly hostile to everyone in that realm. I'm not taking sides and saying who's right or wrong. I understand (at least I think I do) where both sides are coming from. There are legitimate safety issues at play. But you can't be hostile to what's become the mainstream of storm chasing and expect any of those people to ever come here, feel welcome here and stay around - and ultimately be influenced at all. Until we figure out how those two realms can coexist in the same place here, Stormtrack will never stand a chance. That's the other strike that social media has against ST. Those two realms *do* coexist there. Why that's the case is a question above my pay grade.
One practical compromise that might be considered: I think some of the legacy rules of being heavy-handedly stringent on TA threads, while a good thing in ST's heydey, might be more harmful now in a "rebuilding' era. While flames, spam, one-word "cool", "sweet", "wow" posts and similar detritus should of course be controlled, the fact is that in the short term, most every bit of engagement and activity helps ST. Engagement is what drives social media. We rightly worry about us old timers' past stated intolerance for those things, but as I said before, we tolerate far more on social media now. How much worse could a few less-than-academic forecast posts on Stormtrack be?
Conclusion: Chasers use social media because they feel they're getting something out of it. Even if it's just a dopamine hit that blinds them to the realities of a manipulative system designed to exploit them at every turn. Stormtrack needs to offer tangible value that gives them a reason to come here. Doing this successfully without sacrificing any core values will be a challenge, as it means attracting a mainstream that is in many ways at odds with what storm chasing was for many of us when we started. Is it possible?