As someone who lived in Iowa from 1998 to 2019, I genuinely have no idea why so many here see it as this clearly Republican state now ... I mean, it's not the type of state where you can whip out a spreadsheet of trends and swings and make a good prediction, IMO.
I mean, the results from 2014-2018 certainly mean something, no?
2014 was because Democrats didn't seriously contest the gubernatorial race and Biff Brady was a dumpster fire of a candidate. And Hillary was just really hated. 2018 results were actually decent for Iowa Democrats. They flipped two House seats and won three statewide races. I think it's tilt Trump, but it's certainly not out of reach for Biden.