Earlier quoted context omitted.
I don't think this has anything to do with remote vs. onsite work. It has more to do with remote vs. onsite interviews . A thorough onsite interview should catch all of these fake candidates. Companies should be doing at least one onsite interview regardless of whether the role itself is remote or onsite.
A very easy way to verify a remote candidate's identity is to buy them a plane ticket to an in person interview. If they cannot board a plane using their claimed identity from their claimed city of origin, you can stop there.
Are you really going to do this for all candidates that make it to the final round of interview?
Are you also going to compensate the time for the candidate if he doesn't get selected?
Unless what you're proposing is more a formality, and that unless the person doesn't show up he's guaranteed to get the job.