I think the big three are way too powerful and need to be broken up, but doing so intelligently is a tricky problem that I don't have much faith in government tackling.
Zuckerberg integrating all the services yesterday seems to be a transparent attempt to short circuit splitting the company along these service lines, he knows this is coming. I'll bet $100 he'll soon be talking about how it's impossible to split out insta from facebook because of database keys and integrated AI or whatever.