This is vastly oversimplifying things. US would put tremendous diplomatic and other means of pressure if EU does serious harm to tech companies. US-EU and US-China relation is very different.
Even more reason that the EU should work as hard as possible to get rid of their reliance on American companies. America is no longer a trusted partner.
+1
It certainly was very different - maybe less clear that it will remain so.
The whole tariffs debacle, the threat that the US won't back NATO allies in the event of Russian aggression, wavering US support for Ukraine... The EU is starting to see a need to pivot away from reliance on the US.
Without that relationship, a lot of US tech firm offerings are going to look much worse (i.e. we might quickly see an end to overlooking blatant tax evasion and GDPR violations)
Nobody cares about company fundamentals anymore, so for most Americans this would be a trading opportunity. Many will buy the dip and the stocks with rise back even if half of their revenue streams are gone.