Thank you for the friction log! This kind of feedback is extremely valuable!
1. It sounds like you were passing an identity file to --recipients-file. We do support using identity files with --encrypt, but you need to pass it to --identity. We can make the error message more helpful when we notice this is happening.
2. Armoring has a lot of space overhead, and most applications don't need it. (age is not for encrypting messages and emails!)
3. It's now in Homebrew Core :)
4. :D