I don’t use Memories, but yes, uploading photos with FolderSync to Nextcloud (via WebDAV) does add them to the Nextcloud database. They show up as new photos in the recent activities list.

This is interesting to me:

Simpler stack: While still based on the LibreOffice core technology, Collabora Office has no Java dependency, which means a cleaner install, smaller footprint and a single, self-contained download.

Might be advantageous on lower-power machines perhaps?

buttons were discovered by the Conbee and worked perfectly fine, but the home assistant refuses to recognize their functionality.

That’s not the hardware stick; that’s the controller software stack. Sounds like you switched from deConz to ZHA to go with the hardware change. In which case, this is all fixed by using Zigbee2MQTT instead of HA’s built-in ZHA. Z2M supports more hardware and features than ZHA.