Eh, possible, probable, but not necessarily guaranteed. Facebook and Instagram and Twitter and so-forth could survive removing 230, and it could destroy all their competitors in the process, but it would also be very, very costly. Even if they dump everything they can think of into building a great automated system, policing language can be hard as fuck; people can say and allege shit that is slanderous and libelous in a way you can't just run an algorithm to screen for. Handling zillions of takedown requests from companies and individuals would be extremely taxing.
That's part of why they've been sucking Biden's dick so much harder lately. They want to curry favor with Capitol Hill and avoid a lot of this shit, get exceptions carved out for them, so-on. Nevertheless, broadly, I think the concern's valid. Especially since the people who should be defending the importance of 230 to the broader public, as well as the principle of freedom of speech more generally, have wasted a not inconsequential amount of time and social capital on, oh, say, people like Amos Yee.