I do actually have a NextCloud instance, which I primarily use for editing Documents (via Collabora) or syncing backups of folders like Pictures etc from the phone.
SMB/Samba by itself for just sharing folders I’ve had little issue with. Samba as a domain controller with domain-joined clients tied to domain logins is a more complicated beast and - in my experience -prone to breakage in my experience (expired tokens, certificate lifetimes, DNS integration, upgrade issues, etc) BUT it can provide a fairly complete package end-to-end when it works. I just feel that there should be a more Linux-centric/friendly and less bloaty solution that still others decent account-level security.
When you ask “only on LAN” the answer is yes with the caveat that I do also work through VPN, but that’s often functionally the same thing save that the VPN login occurs after the user-login