Everytime recentf cleanup happens, in addition to the usual
Cleaning up the recentf list...
I also see a lot of messages of the form
Wrong type argument: "Wrong type argument", "tramp-file-name FILENAME"
I think it started happening quite recently.
What did you expect to happen?
Recentf cleanup to happen without errors.
Attempt to diagnose
I think the problem is with doom--recentf-file-truename-fn specifically with the use of tramp-file-name-localname in it. I think it should instead be tramp-file-local-name or file-local-name.