More visible promotion of active magazines would go a long way too. Almost every suggested magazine across the top of my nav bar is an empty ghost community, probably made on a whim during the Reddit kerfuffle and then abandoned.
It's still early days, I don't think we're quite doomed just yet. Right now we're witnessing the Fediverse's initial wild west Cambrian explosion sort of era. I reckon eventually the landscape will settle as people flock to where there are already other people, and tools develop and mature to navigate and manage servers/communities.
Obviously we need human mods to weed out morons and maintain quality, but automoderation and other mod tools for spam/astroturfing/etc. will also make a huge difference. A quick google turned up this Lemmy automod which appears to be in active development, and I'm sure there are plenty of others in the works.