I have a couple of friends with nextcloud, and I have nextcloud too. Low tech ish? But we just host our files on Nextcloud and then copy backups to the other machines every now and then.
My NC uses about 6gb of RAM, and it is really badly optimized, since it’s been running forever and isn’t a container, or even a server deploy. (It’s a snap running in desktop Ubuntu since 2016.)
Anyone could do better, I just can’t be bothered.
My buddy has his running on 1.5GB of RAM in a container.
I also host a bunch of other stuff. Navidrome and freshrss get the most use, other than Nextcloud. Immich, searx-ng, jellyfin, guacamole.
Back when I first started with NextCloud, it was pretty unresponsive on the web front end for my ebook collection, which was a ton of small files. It’s gotten a whole lot better in the last year or so. Now, I don’t worry about it. This is also with a very badly set up copy. I’m sure that a proper install would work much better, too.