Also, I run a site at https://fedi.garden that tries to list nice instances organised by various categories like topics, how long they've been around, language etc.
@FediTips What I mean is that servers could output some sort of standardized information with description, tags, etc, and that could be collected automatically.
There is an automated info system, but if there's a bad actor they may lie, or it may be someone originally with good intentions who is no longer moderating. That's why I do manual curation, to check each site before listing.
There are much, much larger directories which are automated and list thousands of servers (for example https://instances.social), but because there's no curation there's also no quality control so it's a bit random whether you can trust a server.