I understand that but with the current president there, calling Biden vice president was just...icky.
It’s like Trump is at a party with his wife Melania and Marla is introduced as his wife.
I think former vice president is fine but otherwise it just seems tacky.
I think it’s just a way for media-types to orally identify the person’s status.
Apparently, if you’re writing a letter to a former vice president, you revert to the highest office held before that singular one. Thus, Biden, Mondale, Gore would be addressed as ‘Senator’ in the salutation; and the envelope would address ‘The Honorable Full Name’:
https://www.formsofaddress.info/vice_president_united_state
(Doesn’t appear to be the same for ‘mere’ representatives :-)