I am in the process of (very slowly) decluttering my life. One weird observation that I had, is that I have very few hardware from the USA, even when I think liberally about "from" as designed and not just manufactured. I found a (crappy) HP printer, (wonderful) Apple hardware and two Zippos. There may be more, but it's not obvious labelled.
Software and some online services on the other hand are different.
From this European perspective the USA is very much a service export and not a stuff export economy.
US invested huge piles of money on the computer age and they cornered the web and software markets and now extracting grotesque profits from it mostly because its a winner takes it all industry. It's not that Europeans don't know how to write software, it's that it doesn't make business sense to go after the established American companies. Linux is invented in Europe, just as the Web but the American entrepreneurs were those who turned these technologies into great businesses. If forced by blocking, it wouldn't take much time to create European alternatives as the hard work of discovering what works and what doesn't is already established. In fact, during the internet age there were many European alternatives for most of it, there's still local alternatives to many.
Take Uber for example, it's not anything special. In places where it's banned, local entrepreneurs quickly made local alternatives.
There's of course industrial software, gaming etc and that's also plenty in EU. It wouldn't take much time to replace everything.
There are plenty of examples from the last 10-20 years where embargoes simply propelled local alternatives even in the most improvised countries.
Americans will have to be stupid to ban software to EU, so it will have to be the EU who bans American software and that probably wouldn't happen until things get really bad.