I realize the anti-Amazon movement was a limited (but loud) group of individuals, but if their level of influence has lasting power, NYC tech is in trouble. Consider NYTimes' own article on the amazon exit. Half the people angry at Amazon were commenting that Amazon wasn't going to pay living wages (thinking that corporate HQ2 jobs are fulfillment jobs.) The other half were angry that Amazon was going to pay too much…
First, agree on the enemy/problem. Then, work out why they're the enemy. This can be xenophobic: migrants, jews, black people, brown people, chinese people, etc. There have been massive popular movements against all these in recent history. They all followed this pattern.
Jews were simultaneously accused of being behind banks and capitalism and bolshevism. Migrants are almost always accused simultaneously accused of stealing jobs and living off the dole. Others chime in that they're destroying or diluting native culture.
It can be more abstract. The problem is capitalism, socialism, monopolies, "corporate greed," the monetary system... Everyone will have their own definition of whichever enemy emerges, and their own reasoning for why its the problem.
Those are extreme and indefensible examples. But, popular movements can also be right about things, while being irrational about reasons.
What we are when we gather politically is... not our best selves.
^btw: I don't know enough about the nyc-amazon affair to have an opinion. Also, not comparing anyone to Nazis.