I am setting ap on Old computer of mine as a local nextcloud instance and maby host my own little Blog. I wouldn't do much else on this machine so I think an immutable Distribution like MicroOs would be the right choice.
What do you use for your homelab?
I would use Debian. Make sure you are practicing good security practices such as strong passwords, containers, vlans, firewalls and least privilege.
I use OpenSuse on allmost all of my devices so I went for OpenSuse Leap, Had problems setting up nextcloud on MicroOs since it does not support snap.
Just use docker and docker compose