One big advantage of IPv6 local addresses is that you can pack a lot of semantic information in an address that's easy to remember, plus bits to help with routing and/or firewalling if you need.

DNS and mDNS don't "just work". You don't need but probably really want HA for DNS which is overkill for a homelab user, and you really want a fixed address for that DNS, because who wants to fix issues when you can't even address your services, and you really want your routers to have fixed addresses for the same reasons; you need VLAN and/or Avahi reflecting for mDNS, and if you need firewalling on your LAN, have fun dealing with the fact that mDNS clients prefer GUAs, then IPv4s, then ULAs in that order, by RFC rule, and managing GUAs sensibly when your ISP keeps changing your prefix -- well, IPv6 is almost 30 years old and home/SMB equipment still can't handle that reliably or flexibly, if it even lets you do anything besides assign /64s, and there's nothing stopping your ISP from saying "here just have a single /64, sorry if you wanted to actually use IPv6 for anything clever like having multiple subnets, who would ever want that?" So you say "I'll just use DHCPv6" and it turns out that DHCPv6 kind of sucks and it also turns out many devices don't support that by default or at all, including every single Android and Chrome device, for starters.

IPv6 is full of these design issues where you have a lot of things that are supposed to Just Work, Look It's So Much Simpler Than IPv4, and look at all these address bytes (excuse us while we take 64 of them away for no reason), except you discover that nothing Just Works with anything else in mildly nontrivial cases. You end up on a yak shave only to discover no yak underneath, and you end up just having a broken network while standing in a pile of yak hair. The whole story above is just one example. IPv6 is a migraine in RFC form, and if it weren't that I accidentally bought some expensive IOT devices that are IPv6-only, I'd be happy to never touch it. At this point, it would have been a better time-money tradeoff to have thrown those in the trash as soon as I had seen the problem.