it’s good to criticize these things to point out that they’re not socialism to reaffirm that division

It is. A lot of communication strategies are worth supporting, because we’re not talking to people who are all in the same place politically. We’re talking to some folks who will still instinctively run from any mention of “socialism,” we’re talking to some who are at the point where the “public healthcare isn’t socialism, you know” conversation is appropriate, and we’re talking to some who are fully on board with the idea of actual socialism and just need to flesh out their understanding of the details.

As far as what amount of Bernie bros end up subscribing to any given tendency of socialism and what just stay libs or whatever

If you’re looking for something firmer than intuitions, here’s an unscientific poll suggesting a huge majority of users here used to be libs. Here’s a post sitting at 2600+ on /r/dankleft about DSA-style folks rapidly running left. None of this is technically data, but we’re unlikely to get data, and I think it’s unquestionable that significant numbers of people who get as far left as the farthest-left politicians in the political mainstream don’t stop there.

something that really is inherently antithetical to it in every way that really counts

This is just messaging, on Twitter. The only possible purpose it can serve is to get people hostile to socialism to soften that hostility. It’s not a serious discussion about what socialism really is – it’s nothing more than “hey think of socialism in terms of things you want and countries you like.” If that gets people over the hurdle of viscerally rejecting socialism on sight, it’s incredibly helpful.