"This also is an issue exclusive to the Fediverse - no centralized SoMe actually has this problem family"
If the issue is "material shared in a particular context is transmitted onward into a different context without asking", then I disagree it's exclusive to Fedi - I've seen that area conceptualised and navigated on Twitter as well. Examples:
• People asking "Okay to retweet?" - not because they legally _had_ to ask, but out of sensitivity to whether the OP _wanted_ their post shared further. Often used for posts where a personal anecdote was shared and other people find it especially illuminating.
• Quote-tweets being used to focus attention on a tweet - widely considered an affordance which can be used for good or evil :-)
Or are you thinking of a _different_ issue?
