I’ve been running Nextcloud for months on a SYS ARM storage server.
ARM-2T Server - Cortex A9 - 2GB - 1x2To
It suits me fine, as a long-term storage server. All that interests me though, are encryption and consistent, predictable storage. I stagger the access, from VPS, so only one client at a time and run a custom kernel that makes better use of the available network speed.
Upload performance, using rsync mirror, through a davfs2 mount:
2,724,863.79 bytes/sec total size is 19,061,399,207 27m41s
(Just for your benefit…) Downloading an 1.8GB ISO, via Nextcloud web interface, to my laptop at home:
It’s a different use case than yours, OP, but may be of interest. Generally, it’s a bit sluggish but it’s not horrendous, by any means.