If you had an account and then deleted it, you will get this page until you delete you beehaw cookies. It tries to automatically log you in on your old account and then fails with this error as it was deleted.
I’m not sure if this is unique to beehaw or across all Lemmy instances.
I’m not sure this is true. Like imagine someone posts their address in a Lemmy post - I’m pretty sure that counts as PII and they have the right to request its deletion.