I’ve tried Nextcloud before and was disappointed with how it handles syncing large volumes of files, like photo galleries. I wouldn’t use it for that again, at least not in its current state. But Nextcloud does much more than file sync.
It comes with a suite of official, one‑click apps, and I was particularly drawn to “Contacts” and “Calendar”. That’s exactly what I’ve needed for a long time: a reliable, self‑hosted alternative to Google services that can keep my Debian laptop and LineageOS smartphone in sync.