It's a different world from the 80's, tbh, the polarization is palpable. Reagan won his '80 election with almost a 10 million vote difference. His re-election against Mondale by almost 17 million.
Realistically, I think Trump's trajectory is to disappoint in the long run. Eventually, people will tune him out for one reason or another (the base will always be there, though). It's not just him, happens to almost everybody in public office after a while. I understand the current excitement over winning an election that seemed out of reach for a while, but this stuff tapers off with time. I think what eventually will make or break his administration is what he's able to achieve in the economy, and him not actually being a typical conservative when it comes to things like spending, will encounter some resistance (don't forget dubya cut taxes too, splurged in things like Medicare part D, and ended up being called a RINO). I hope it does work out though, we all could use a better economy. I mean, I would've expected the same from a ty candidate like Shillary. I think anything past 4 years would've been extremely dubious.
All that said, if the Dems don't get the Clintons out of the way (and the Obamas too), and move on to the new crowd of candidates (which they have a few), then that's a self-inflicted wound, IMO.