rclone's documentation warns you that you can't actually get the original resolution photos back out via the Photos API. Better than nothing, obviously, but...
... just a confirmation that signing for anything on google just makes you their hostage. I'm happy I quit them 5 years ago after I couldn't have access to my mail anymore after I stepped down my paid drive access to free one and I didn't have space anymore to receive emails.
Because that hit you by surprise, or because you intended to keep all those photos while on the free tier?
It seems to me like deleting the files over your storage limit is the easy path for both you and google and I don't see how this is an example of holding you hostage. At most bad communication and a lack of warning.
Don't remember exactly but I was expecting not the two services being linked. IIRC I already downloaded back a lot of pictures and my free plan was something like 99% full. The fact that Google blocked my email reception without any notice was hard to swallow.
To be sure I backup my phone's photos using rsync (via termux) to my own backup locations.