He went after big tech as a punishment for fact checking the bullshit coming from his administration and his followers. That was it.
Now that all big tech has turned away from democrats (probably as punishment for their antitrust lawsuits), we will see a much different perspective from the Trump administration.
I don’t think so. There’s no good alternative to Facebook that is worth leaving it for. When MySpace died, there was a significantly better alternative (FB). Even if people quit using Facebook regularly, they’ll need to keep it.