Most of them were already Republicans and will stay that way. The Obama-Trump voters will split three ways, with a third going Republican, a third going back to the Democrats (if they hadn't already in 2018 and or 2020), and a third not voting at all.
I agreed with the 'three-ways" part just not with the proportions that follow, specifically the ones that will vote democrat or will not vote at all. Trump's base blames Democrats for a lot of the "obstruction" and believe in some deep state that is out to get them, and I personally think a large chunk of them are uneducated Obama-Trump voters. I would more realistically split these groups as 75% of them voting GOP, 10% becoming swing voters, 5% going back to the Democrats, and maybe 10% of them not voting. But to say 33% of them wont vote, in an age like this, is quite an extravagant statement.