Can you check in a terminal? If you can see them in the terminal and not in the desktop you’re missing a font. If you can’t see them in the terminal then you’ve somehow mangled them. What was the OS and filesystems you copied from?

It has absolutely never happened before that one guy had to spend some time in a government facility. No. Not at all.

Try putting -vvv when you connect and see what’s happening. I can imagine this happening if you have multiple identities (private/public key pairs) on the client and you hit a max retry limit. Pub key is always tried first, and it should ask for password once all the local keys have been tried.

Which distro?