> This argument feels theoretical.
So does your argument.
> Twitter is not just an ad network. It offers unique values to its users.
Yes, it does, and that unique value is noncommercial organic content, which charging for organic reach undercuts.
> If twitter starts charging the followers, sure, that will be a big mistake. I'm not suggesting that.
No, you are suggesting something just as bad: charging people for exactly what gives the followers a reason to be there.
> If twitter starts charging the followers, sure, that will be a big mistake. I'm not suggesting that.
They are producing and providing Twitter with content which people are coming to Twitter to consume. That’s not “wasting resources”, that’s what enables Twitter to sell space to advertisers.
> By the time they're big, they will value the relationships they've built with their followers.
By the time they are even moderate-sized, they’ll be on multiple social platforms, be using each of them (among other things) to inform their followers of the others, and the kind of content they are distributing on them (especially as it changes), and will be, themselves, cobtinuously reevaluating the cost/benefit of each platform for particular content and adjusting their social media strategy.
Facebook uses this strategy, and as they dialed it up, big accounts did direct followers to other platforms to get reliable access to what they were producing.
> A generic social media firm couldn't do this, but twitter is in a unique position.
How? Literally everything you’ve said applies to any large social media platform the same way as it applies to Twitter.