Dumb people

Lack of critical thought or many even more likely lapse of critical thought.

Scaling solutions not being ready.

Humans lol

Human apathy, cognitive dissonance, and stupidity.

Social. For example when mainstream media starts vilifying Bitcoiners when everything is crashing and Bitcoiners have been celebrating. The parallel from history is Jews making sound financial decisions in the early 30's in Germany.

Governments choking odd on and odd ramps or outright outlawing it

A US government ban would really hurt, but it would not be fatal. Just a big setback. Love the show dudes.