nixon supposedly told trump he should run for president, so maybe in this atl trump is elected in 2012
obama losing reelection would be big, since it'd indicate dems' doing the corporate identity politics gimmick doesn't work. much less "wokeness", more social liberalism of the hedonistic sort -- 2021 looks much like 2009 or 2010 with current technology and more liberal attitudes on lgbt/weed
a better world, much less censored internet
Except:
The time really wouldn't have been right for Trump in 2012. Anger at immigration hadn't boiled over, ISIS wasn't on anybody's radar, & the general feeling was that things weren't good but they weren't getting worse. That had changed for many of the people who mattered (& propelled Trump to victory) in 2016. Had he ran on the same populist platform, he would've lost the general by a significant margin.
And the birtherism thing was also something that most people, regardless of their views, thought was ridiculous & wouldn't get behind. Birtherism had a peak, in mid-2009, as the Tea Party rallies got a bit out of hand, but afterwards, it was widely discredited & even the most populist voices on the right (like Limbaugh & Hannity) were calling it out as dumb.