The US tech industry doesn't have as much leverage as they think they do, the hardest part to replace is the hardware, which mostly isn't built in the US anyways
That reminds me of Mark Zukerberg which threatened to leave a while back... and denied it soon after realizing the bluff didn't work.
When I worked for big tech the US was always the most profitable market, usually followed by the UK. Albeit that was a long time ago. But the EU has economically declined since so I doubt things changed much.
Again, I've been away from FAANG for a while, but the EU (note that this is 27 countries) was super, super profitable.
From an ads perspective, you made money from selling to a bunch of relatively rich consumers (the EU) AND (this is more important), lots of EU companies spent loads of money on US advertisers. This is what pushes up prices and thus revenue in the EU.
Yes, the US consumer does spend a lot of money, but their super high revenue from tech is more a function (rather like their equity markets) of lots and lots of foreign money coming in.
I leave it as an exercise to the reader to think about what happens to these markets if/when the Europeans stop spending as much money in the US market.