I don't think you are nutty, and I'll agree that the current wave of (rather childish in my view) enthusiasm for some of the equivalently childish new wave of Democrat "legislators", does indeed suggest that something lasting may have changed. Stranger things have happened - the 13th century Children's Crusade comes to mind, as does the enthusiasm among first century BC Romans for the parade of Triumvir dictators who promised to end the sectarian strife that, with systems that ensured compromise, had been the foundation of the Republic for centuries, and who instead delivered civil war, dictators and empire. In more recent events, there was also the exaggerated public enthusiasm Lenin, Mussolini and Hitler. On a smaller and (in historical terms) still incomplete scale, for Presidents including Wilson & Kennedy that has faded with time and analysis of the results they achieved (and the corresponding growth of respect for others, like Truman, who was much reviled by contemporary "analysts").
The public view of the so called "millennials" is also in my opinion a bit distorted. We have had to deal with many in my company - mostly graduate Environmental Scientists, Geologists and Engineers. My strong impression is that their (often expressed) sappy views fade quickly as they are faced with real responsibilities and accountability for projects (at least among those who survive). In addition we are recently seeing a second wave of neo conservatives among them who, in contrast, appear weary of all that ****.
There's no denying that your Bernie has ignited a new enthusiasm for government managed 'solutions' to an increasing array of social and economic issues. So far he has offered very little in the way of details regarding how such distant goals will be achieved, and none at all regarding the inevitable side effects of trying. It is worthwhile to note that the only jobs he has ever held were as Mayor, a Congressman and later a Senator. He has no experience in the real world of social and economic achievement.
Deserved or not I suspect his new competitors for the Democrat nomination will be strongly inclined to point out whatever contradictions or issues they can find in Sanders' career (and perhaps also that of his wife), all in an effort to discredit him and replace him themselves. In my view his long term tenure as leader of the Democrat Left is unlikely.
I'm also not sure the current public enthusiasm for Government managed "solutions" to social and economic issues will last. Increasingly perceptions of their inevitable intrusions on individual freedom and their usually unanticipated adverse side effects are being recognized by the public, Consider that so soon after the 2007 deflation of an economic bubble in the real estate market,- due entirely to the infusion of cheap government capital - we are suddenly surprised to see the same thing happening in university tuition with government managed student loans. Both failed to achieve their intended purpose and both had their victims - homeowners faced with underwater mortgages, and graduating students, burdened with debt.
I agree the unfolding political action in the country as we head towards the next election will remain very interesting. With their large (and still increasing) field of announced contenders Dmocrats face, to a greater degree, the problems Republicans faced in 2015 with their large group of contenders - a situation that left the party very disunited in its aftermath. Now, in the face of relentless refusal and hostility from Democrats, both publicly and in the Congress, Republicans are far more united than they have been for a long time.
What will come of all this is something I can't predict accurately. It will be very interesting to see what unfolds.