1. Trump's legitimate election in 2016 - see all the hysterical reactions like "Not my president" protests or urging faithless elector to vote for anyone else but trump route or "Russia-gate" (left's Benghazi?) or the impeachment farce. (I don't think I need to provide any citations here).
2. Illegal immigration - left doesn't acknowledge that this is a problem. And then you see left's contradictory messaging ("illegal immigration has slowed down to a trickle") to thousands of children showing up on our borders. Couple that with ridiculous demands like "Abolish the ICE" or calling Obama the "Deporter in Chief". Concrete example of a prominent leftist: https://www.newsweek.com/aoc-abolish-ice-hysterectomy-whistl...
3. Economics: there is a broad agreement among the economists (including someone like Krugman) that rent control doesn't work. Yet you keep seeing repeated attempts from the left. Latest example: CA Prop 21.