Easy to say, harder to execute. Network effects keep American companies as the main way people communicate, whether it's WhatsApp, Instagram, Facebook (or Facebook Messenger), or something else.
Russia and China have nation-wide firewalls. I know that at minimum, China blocks most or all of Western social media sites. I don't want to live in a bloc of countries that blocks parts of the web "for my protection".
It's easier for politicians to write laws forbidding stuff and pat themselves in the back than radically changing the economy to foster innovation and investments for EU-based tech companies.
Every other country has their own ecosystem, EU seems to be capable enough.