I’d go for syncthing over nextcloud for your specific usecase. Nextcloud isn’t good for unreliable connections and they’re sticking with the annoying decision of not supporting server to server synchronization.

Lol why are people such dicks? My vets sent pics when my dog was recovering from an operation. It’s a pretty normal thing.

Anyway, if it was me I’d just set up a stream of the webcam on peertube via OBS.

I don’t know how far owncloud and nextcloud have diverged, but in the nextcloud client you can add filters to ignore files by clicking the three dots on the folder in settings.

You can also free up local space by using virtual folders, but it only works properly on windows.