I think that's totally reasonable, but I'm still left wondering when and how states should actually carry out purging their voter records. Would a year before a presidential/midterm election be fair? Six months? What about primary elections?

As for same-day registration, I'm sort of for it, but only if people understand the cost involved. And it's not about money. I served as a poll worker in California many years ago, which has very accommodating rules for voting. You can register same-day, vote out-of-precinct, the whole smash. It makes it really easy for voters, which is a good thing. But it has a price: it makes the check-in process more complicated. If there are a lot of people who need to do same-day registration (as was the case in my precinct when the city renamed a street a few weeks before the election), then it causes long lines.

Why would you do it before major elections if it's just about book keeping? You could purge them a month after mid-terms and a month after general Presidential because those get the most turnout.

When you purge your voter roles becomes a lot less important if you allow for registration/reregistration on election day regardless.

Oregon has same day registration update (and we have motor voter) and no long-lines because we vote primarily by mail.

Disenfranchising voters to 'avoid long-lines' is just a red herring.

There are lots of ways to create quick, safe voting. Election problems are the result of a deliberate attempt to make voting harder for certain people. Full stop.