Nah, this can lead to having many sparsely populated communities. It can discourage new users, and fediverse adoption generally.

For example, if you look in one of the several audiobooks communities you would conclude that the fediverse is a ghost town. However, the actual "community" is in /c/books. If you post about audiobooks in both you won't get any engagement in the audiobooks communities.

After the great reddit API influx a few years ago a bunch of communities sprang up but were quickly abandoned, contributing to this problem.

There's actually a community discussing these dead communities and how to go about merging / closing the dead ones, but I can't remember what its called.

Of course in some cases with larger communities it might make sense to split communities into different topics, but there's very few communities large enough for that to be genuinely warranted.