Mail in ballot counts are down in every state from 2020 to 2024. In the all mail elections (actually you do have the option to vote on election a limited number of sites) states of OR, CO and WA ballot returns are also down. So those states like NV and CA that have either at or above 50% are also down in ballot returns by mail. I am getting the idea that the glow of using mail in ballots is fading. I do note that the mail in ballot option provided the Ds with a huge turnout boost in 2020 and those voters provided the biggest margins for the Ds in the states that separated the numbers.
There is no doubt, look at the turnout numbers among certain groups of voters in CO/WA/OR, that putting a mail in ballot in the hand of voters helps the Ds by generating turnout in categories of voters that favor them. I think it’s a two step dance as to why ballot numbers are down. 1st it appears that those voters are less interested in voting this year. The second step and this applies to mostly voters outside of the mail states is that the effort it takes to vote by mail is only a bit more than the effort to vote early or in person.
I think the other consideration is COVID in 2020. Maybe people really do prefer normal voting and what happened in 20 was a fluke driven by COVID.