Can be a good idea to check here
https://haveibeenpwned.com/
See if email addresses you use may have been included in a data breach of another company after they were hacked.
That’s how these “I saw you watching porn” scams work, as they are mailing you with a password you know is / was correct, because they have acquired it from a data breach somewhere.
It’s worth resetting passwords, or enabling two factor authentication wherever you can.
Like others have said, you can ignore the muppet