EU countries should start fining and taxing these US tech companies heavily to force them out of business in the EU and leave room for local EU competitors. The EU should try to be more like China.
I'm sorry but that's bullshit. Almost by definition, whatever replacements would be created would be inferior to the banned originals.
If you start using fines and taxes as instruments of protectionism, you've also become a country no longer ruled by laws, but by the arbitrary whims of whoever is in power.
I already spend too much time online defending (for example) the EU's antitrust policy against accusations of nationalism. If that sort of thing really did happen, it would be the start of a trade war. And nobody is interested in a trade war, except those whose thinking is impaired by some rather anachronistic xenophobia.
Specifically for Facebook: about 40% of my friends are outside the EU. I wouldn't create an account on any social network that they are not on.
EU countries should start fining and taxing these US tech companies heavily to force them out of business in the EU and leave room for local EU competitors. The EU should try to be more like China.