I also just do this. However I have already found 2 photos that got randomly corrupted, and I don’t know how to prevent that.
So far my only idea was using md5sum, but checking all files like that takes a loooooooooong time.
I am paranoid about cloud. I do have my music backed up on OneDrive, encrypted with GPG using AES256, but I don’t even fully trust that. I know, it sounds stupid, but maybe in the future it will be quite easy to break.
But I don’t know much about encryption. Just reading the man page, I put these options together: