What tools? The ones I use are done from people all over the world, certainly not predominantly in USA.
Z-E-R-O.
I don’t even think companies have their own mailservers anymore, its mostly gsuite and microsoft office 365; people aren’t even hosting business critical applications in Europe unless compliance forces them- let alone using European made tools to do it.
There's a lot more to life than a lot of things, I'm not really trying to discuss personal fulfilment, moreso mentioning that there's no reality where we can get by with European technology right now, and if the US decided to sanction a european country that country would suffer a pretty significant (trillion-euro most likely) shock to productivity, as not only would they need to find new tools and retrain, but they would also lose all their mail and documents.
If the USA sanctioned europe (lol) we'd be completely fine, don't worry.