There are some subtle nuances when managing nextcloud on OpenBSD. Mostly, they pertain to understanding and working with OpenBSD's permissions philosophy. But once you grok it, it's a relatively smooth ride. In fact, I've had more problems with the Nextcloud software itself than OpenBSD.

I have found running OpenBSD as a server very rewarding. If you plan on going down this route, just ping me; I will try to help you out wherever I can. I also recommend asking questions in the #nextcloud and #openbsd IRC channels on libera.

Good luck. You can do it.