Trump’s EOs aren’t where the rules will be set (hopefully, unless the SC just fully declares the Constitution void). It’ll be a the states. And they’ll design the laws on who can do mail in voting to their benefit.

For example, Georgia, with its red trifecta who would like more red votes to be counted both for their own elections and the House, passes a law saying it’s only valid of you live in a settlement with less than X density. X is above suburbia but below cities. And since it’s targeting areas rather than districts, the gerrymandered districts can boost their red votes and suppress their blue votes.

They don’t really care about voters in LA, they care about suppressing Atlanta and Austin so red states stay maximally red. They don’t need to take over blue states, just maintain their current dominance despite the electorate turning against them.

If voter suppression reliably caused the offender to lose no one would do it. But it doesn’t, not when applied subtly and accompanied by spin about how it’s just saving money or securing elections. The people on the margins who are most likely to stay home rather than go to the polls are the same ones who aren’t passionate about voter access and voting in general.