Struck by a conversation today with more senior academics about the impact of social media; Their sensible response was, "I'm off twitter, we should turn off twitter" where I made the point that for on-the-job-market junior academics, turning off Twitter may not be an option.

I don't think their response was in any way wrong, but I think it speaks to how precarity shapes everything else in academia.
For junior academics whose networks are necessarily limited and who are in an extremely competitive job market, Twitter may not be optional.

I know I'm unusual in this regard to some degree, but Twitter has been a pretty important professional networking tool, especially during COVID but even now. Conferences are expensive, but Twitter is free and I've gotten invited talks and conf. panels via Twitter contacts.

Given that the academics on twitter skew mostly earlier in their careers, I'd expect this effect to intensify over time that folks on the job market or with a book coming out may feel they have to be here and to a degree have to be active here.

That's not an entirely terrible thing - Twitter is a public square of sorts and I do think academics should engage more with the public (though only a small slice of the public is here), but it means that it is hard to confine toxic habits of academic twitter.