

You can only filter and sort what was downloaded by the client. So that runs into resource constraints.
There shouldn’t be resource constraint issues in downloading new content Metadata from all your subscriptions
tags
When I say “standardize tags on all content”, what I mean is make it a standard to have the option of having tags on every type of content, and treat tags as a first class attribute of the content. The XKCD you reference is not relevant.
That’s more the ATproto/Bluesky vision.
Sure, they use it. But it is compatible with activityPub as well.






I think having instances or communities dedicated to that would be wonderful.
I think having separate identity providers would work well with this. Those identity providers could optionally verify age and location, and your instance can just trust them on that to make it exclusive to certain ages or locations.