I don’t actually believe in the “overton window” I was most just using it as shorthand for the idea that some of the people who got hyped for Bernie moved on to actual socialism.

This is idealism i.e. by being exposed to Bernie's ideas some people were able to move on to socialist ideas

That isn't what happened. Bernie is an effect, not a cause. Bernie's popularity came from the worsening material conditions, he didn't just hype people with his good ideas and conjure his own popularity up from nothing. Material conditions are now even worse, so now people are moving on to actual socialism. If the so-called """overton window""" can be said to exist at all then it is moved by the underlying material conditions, not by ideas.