It would be inexcusable to write off MI/PA/WI, all of which were within 1.5% and all of which are still perfectly winnable for Democrats in 2020 as long as the Democratic nominee campaigns there and takes those states seriously. As for AZ/GA, put together they can definitely be a replacement for IA/OH, which for the moment seem to be slipping away from Democrats (though these things can sometimes reverse themselves) -- 2020 seems to be a little too early for GA, which'll still be a leans-R state at that point, but AZ will definitely be a swing state and it would be inexcusable for Democrats not to invest something in that state.
The 2018 Senate race in AZ is going to be very telling as well. I'd imagine Kyrsten Sinema is licking her lips to run against a divisive Republican incumbent in a Trump midterm. If she can't make it (or if she decides not to run), that would be a very negative sign for Democrats.
No, if Trump continues with what he did with Carrier the Midwest will be solidly GOP in 2020 because muh jobs.
