As it is now, it’s quite inconvenient to not be able to see a community’s actual subscriber count from an instance and instead see how many are subscribed to it from the current instance; makes it hard to judge their activity from a search, and is confusing for new users.
A shared user count directly in lemmy would be very useful.
Mastodon doesn’t quite have a “popular toots” tab, and until recently there wasn’t a list of recommended accounts from other instances. What it does have is a list of popular hashtags.