Interesting, didn't know "iCloud Backup" could be self-hosted. I'm self-hosting everything else except for that one item on the list, I might as well make the jump.
I personally like how iCloud automatically backs up my iPhone whenever it's charging and connected to wifi.
[1]https://support.apple.com/en-us/HT210612
[2]https://nextcloud.com/install/#instructions-server
[3]https://github.com/duplicati/duplicati
[4]https://www.backblaze.com/b2/cloud-storage.html#why-b2-menu2