This is a real need. Nextcloud barely even works. File search craps out all the time. A simpler solution with just file preview and full text search would be awesome.
Recently Stalwart got a grant to work on adding WebDAV, CalDAV and CardDAV and I’m looking forward for their progress as they seem to be talented by the look of their email server implementation. Hopefully they can develop good client side software too if it’s in their scope but slightly worried that their scope is getting rather big to be a replacement of the Exchange environment.