If back to the future was released today more than 1/3 of the population would root for biff and would say that the movie is “too political” and “woke propaganda”.

That was half the joke of the original movie. Biff got super rich off cheating at sports gambling and was rewarded for his sudden financial success with political authority, because the writers of the movie knew that's how Americans respond to anyone who appears to be financially successful practically overnight.

Biff was a critique of the people who elected Ronald Reagan. People who were saying exactly the same fascist shit as MAGA Trumpies today.

Then again, being OK with child rape by that same group of people wasn’t something I would have expected even 10 years ago…

You must have slept through the whole Catholic Sex Abuse moment. The sex-crimes apologists were crawling out of the woodwork. Guys like Ross Douthat made their first nut trying to defend the indefensible. Half of the Peggy Noonan columns were just her whining about anti-Catholic bias every time another child-rape story broke. JD Vance made his Catholic Turn right in the middle of the scandal, seemingly to suck up to the rich Catholic fuckwits gullible enough to believe he was going to protect them.

Before that, you had the string of scandals at the Texas Youth Corrections office. And the Abramoff Scandal, which had an often-undercovered element of child sex trafficking in the Marianas Islands. And, of course, Epstein himself got off with multiple slaps on the wrist across multiple administrations, thanks to his DC (and Mossad) connections. All these people and institutions retained conservative support in the face of a deluge of accusations and a torrent of new victims coming forward.

Biff has a certain amount of sympathy from me. At least in the first one.

Biff engages in some morally unpleasant punching-down bullying. In return Marty breaks the laws of continuity and fucks up his whole bloodline.

Its a pretty disproportionate response.