"USPS will be swamped"
by maybe 50M mailed ballots.
The USPS handles 2.5B pieces the week of Christmas (50X, for the math challenged).
The vast majority of people who have requested ballots by mail have several weeks to return them and in many places can return them in person.
None of the states that send "unsolicited" ballots will matter in the Presidential election. Although none have ever detected more than the tiniest amount of fraud.
BTW, it was a shame about the postman in WV who Dennison referenced- he changed five ballot requests from D to R. And he was arrested.