Nextcloud always fascinated but it just never really worked in its entirety. Webdav is slow and requires re-syncing entire files every time a change occurs. The Nextcloud sync client on all platforms has issue after issue with syncing and don’t really trust it, especially as files get bigger (anything over 10 MB). If you open the Nextcloud client and need to sync say 50 GB of data good luck closing the client and opening it next day, or even next minute and expecting it to pick up where it left off. All kind of errors will be thrown (even with Apache optimization). Again this is webdav. This obviously doesn’t scale well.
But one neat thing about Nextcloud was being able to access data in browser like Google Drive. This is what liked about Nextcloud. This part of Nextcloud is a great replaced for Google Drive or Dropbox, the Nextcloud sync just never was or is. So combined Syncthing with Nextcloud. Syncthing is just amazing for syncing files. It works flawlessly and never had an issue no matter the size of file. Can close Syncthing and reopen it next day and it picks up right where left off. And its actually easier to setup Syncthing sync than Nextcloud sync.
So now run Syncthing as www-data user on Debian server on top of Nextcloud. Syncthing syncs beautifully between any device necessary and can use the web interface of Nextcloud when necessary. Wish didn’t have to run a server (the strength of Syncthing in most cases) but once set all this up (which wasn’t very hard or time consuming) it runs itself and can utilize the best of Syncthing and Nextcloud.