For those who wish to eliminate vote by mail, remember only the individual state can make the decision. it is not something that can be done by Federal action without a Constitutional Amendment, passed and ratified.
Here in CT, we have very restrictive allowable reasons for issuance of a mail in ballot (absentee):
Absence from your town the entire 14 hours polls are open
Illness or disability
Military Service
Religious conflict/obligations
Being a poll worker (municipal, not political party) at a polling place not your own.
Having been an Asst. Registrar of Voters for many years (which our town assigns to polling places outside our own to avoid appearance of conflict), I have voted by mail for many years.
This year our Governor extended the illness/disability provision to include concern for contracting Covid-19 for 2020 elections, primaries only and anyone could apply for a mail in ballot.
In 2014 we had a ballot question to amend the state Constitution to allow all to vote by mail if desired as a matter of convenience. It failed to pass.
It will be interesting ti se if the legislature takes this up again in the 2021 session and if it is on the 2022 state ballot