There are other problems with mail in ballots besides getting lost in the mail.
1. Not showing up personally with valid photo ID means anyone can fill out ballots and sign them.
2. People can be coerced or pressured into filling out ballots such as in nursing homes, etc. May be registered voters but very dishonest.
3. Ballot harvesting - third parties collecting ballots from others (what others??? the dead? Homeless? Illegals?) and putting in the mail or delivering to polling places.
4. Ballots filled out by operators that were never even mailed to registered voters, and then the registered voters real ballots thrown away and/or nullified.
I’m sure there are more ways to cheat even if the mailed in ballots are properly delivered, these are just off the top of my head.
all good points
plus dems have many more ways to cheat