Most stuff is. Even some people and companies in Europe had a hand in building it; at the very least I'm sure Apple has software teams there, and ASML is dutch.
We're a deeply interconnected world. Few parts of it can be self-sufficient while retaining the standard of living they're used to. This is true for no region more than Europe. Europe, broadly, relies more on the productivity, output, energy, and innovation of America and Asia for their standard of living than any other region, including America and Asia on each other or on Europe.
The iPhone is an interesting example because Apple's Asia sales did drop last quarter; but that drop was compensated for by a ~$3B increase in European sales. That's the trend I'd bet money on continuing. Europe doesn't have any other choice, and except on some fringe issues Europe's purported culture and values align far more with even Trump's America than China. Europe cannot afford to not pick a side in that adversarial relationship.
Tbh, Europeans broadly trying to boycott American companies gives real "toddler throwing a tantrum because his parents made him eat broccoli" vibes. At best, its unserious. At worst, its only going to harm Europe. Europe should make efforts toward reducing its dependence on the rest of the world, but their leadership is deeply unserious about doing so, and even if they became serious it would take many decades to reach even the only America or Asia is at.