Upside is that this change would effectively consolidate small communities across instances so they aren't so fragmented.
Downside is that there would be less control over what content is tied to each tag because I'm not sure how moderation would work. You can end up with issues where people maliciously flood a certain tag with junk.
The upside of communities is that each can moderate themselves, and you can block the ones that don't moderate to your standards.
Upside is that this change would effectively consolidate small communities across instances so they aren't so fragmented.
Downside is that there would be less control over what content is tied to each tag because I'm not sure how moderation would work. You can end up with issues where people maliciously flood a certain tag with junk.
The upside of communities is that each can moderate themselves, and you can block the ones that don't moderate to your standards.