Not sure I would agree with the socialist boogeyman theory.
4 million new millennial voters come on line every year. Boomers numbers will be reducing. Millennials have a higher favorability for socialism than capitalism. It's an entirely different set of economic circumstances facing them than faced boomers.
Sanders ran as a democratic socialist and didn't seem to have much of a problem with it. He had more problems with the press and DNC than with voters themselves.
I just don't think red baiting is the handy tool it once was.