two examples: https://mastodon.social/@kradeelav https://mastodon.social/@chirart
I don't mean to advocate for Mastodon or anything else in particular, but these things sometimes have a way of being niche until they're not.
I also think part of the parent's argument was that in encountering obstacles like this, groups of nonprofit institutions such as art museums could leverage their position to promote decentralized systems, rather than simply throw up their hands and go with a sensationalized move.
Then again we are here discussing it. But then again if they banded together to post on some decentralized platform we'd probably be talking too.
There's no reason social media shouldn't be more decentralized and federated. European institutes can and should consider open source, federated alternatives unless they want to be forced to play by the rules of the big social media providers.