This is part of the answer.

I have a theory about the second part; European consumers have an even more suspicious view of "corporate overlords" if they are domestic/European than if they are American. Not because Americans are more trustworthy, but because they see Europeans as "anonymous masses" and are therefore more "neutral" to the internal struggles in Europe.

Signing up to a service owned by a European "dynastic" family, possibly in a neighbouring country, feels like more of a surrender of autonomy.

Hasn't this also something to do with the cultural dominance that US have had over the EU? We considered US services more valuable just because they where from US. But that cultural dominance might not be as strong anymore, maybe because of social media/TikTok?