[Ourgon]

If ever you get tired of Google - and for those who get tired of Apple or Amazon or whomever they have entrusted their digital photo archiving needs to...

Any of the personal cloud things - Nexcloud, Owncloud, Seafile, Syncthing and others - can be used to sync files - and with that photos and videos - from mobile devices to some server somewhere. This can be the server-under-the-stairs, your NAS at home, a wall-wart with a Raspberry Pi and a drive taped together, a VPS or a commercial entity offering these as SaaS. You can keep using your phones with or without Google, that is up to you. If you run the stuff yourself you'll need to install and configure the parts which make it work, if you use a commercial instance you just have to install the relevant app and tell it to sync your data. You can do this in parallel to using Google Photos, just to make sure you have a backup in case Google wants just that one extra piece of personal data to allow you to access your photos which makes you give up on them. Just one more piece... and one more please...