I have been using an old PC as NAS and running docker containers (Immich, Nextcloud, paperless-ngx etc.). I got 5 3.5" HDD disks and a Nvme. Even on idle, I am consuming 50-60w. A friend of mine is selling a Qnap NAS which is a dedicated machine and probably consumes less power, although I don’t know if it’s worth it.
I remember to have it working with default software I got but it was 10 years ago. Then they added this bloatware like media streaming addon or notification center. I have now entware with minidlna and set minidlna scanning disk once per day because media streaming was scanning all the time. I haven’t figure out how to permanently kill their /usr/local/sbin/ncd, ncdb, qNoticeEngined, qulogdb, NotificationCenter, mariadb processes. If I figure out it it probably start working again.