What you are describing is NOT an election! You are describing a contest of who can gather the most ballots for your team!
Rules are rules. Ignore them and lose. Play by them and win and you get to change the rules. It is clear that there is pretty significant support for mail in voting. But there is a right way and a wrong way. To ensure it is done the right way we have to put elected officials in place to write and/or change the laws. Can’t do that in close elections by conceding part of the playing field.