I use syncthing for this exact purpose. Its p2p, so it requires no hosting experience, and can sync to any number of private or public devices. Just sync your main camera folder to any (ideally always-on) PC, laptop, a secondary phone or your friends/families devices.

mp4 files generally get corrupted if the recording isnt properly ended, so i have my camera app set up so that it starts a new file every minute or so. That way even if my phone is destroyed/snatched, the last clip that makes it to safety is pretty recent.

Syncthing website - https://syncthing.net/
Syncthing Android App - https://f-droid.org/en/packages/com.github.catfriend1.syncthingfork/
OpenCamera - https://f-droid.org/en/packages/net.sourceforge.opencamera/