Is that really the case for the EU? The EU doesn’t seem to foster an environment for competitive companies that can operate at the necessary scale the above listed can.
The EU has many competitive companies, I think HN is too focused on "tech" as in digital/web stuff and quite blind to other technological industries...
You’re correct that few EU companies get as large as US monopolies, but that’s kind of the goal when you want a functioning market.
So yes, just tariffing or restricting US tech wouldn't help much. Europe "lost" that race fair and square. It needs to focus on fixing all those things.
I personally don't want the EU to become the US. And Investors gambling with other people's money is what gave us the world financial crisis of 2007. No lessons were learned as usual.