Never rely on a single cloud service for your backup. Always backup to at least one independent place such as a local hard drive or another cloud provider.

This. I suggest iCloud, Dropbox, Lightroom, OneDrive, or Ever. I often take advantage of “free trials” to upload all my photos to these services periodically. Once your free trial expires you can’t upload more photos but they hold onto the existing ones indefinitely.

I also use a NAS device (cheap!) and a lifetime Plex account for my viewer. Only iOS “live” photos are inconvenient to back up anywhere but iCloud so I don’t take many Live Photos.

I have all of my photos in a RAID 1 at home, and I regularly "rclone" all of them to Backblaze B2. I have all of them inside Google Photos because that's how I view them, but I don't consider it to be a backup. It's just a much more convenient way to access the photos from many devices, and share them with friends and family.

Apart from that, I keep a Google Takeout archive the same way (RAID 1, B2)

Google Photos is not a backup system. It’s a place to host photos in the cloud. You need your own backup somewhere else.

Don't keep your photos in only one place if you care about them, even if that place is Google.

Google Photos is a handy worst-case backup for your photos, but it's not magic and you really need to keep another copy somewhere.