This whole debate originated in some people noticing that there was a lot of wrongthink on the internet and then starting to yell at tech companies for not fixing it. But it turns out that problem is legitimately hard and the tech companies don't have a magic wand, so all their attempts have been ham-fisted disasters that trample all over everything like a frightened elephant.

That problem in particular isn't really one that competition would solve, because it's fundamentally a demand for censorship, and more competition would make censorship harder. Which is maybe a good thing anyway.