I'm not sure there's a direct correlation. However, I will say I think the left has lost their minds a bit on identity politics. Hillary Clinton would have won the election had she run as her husband's campaign of 1996. Of course, her husband's '96 campaign said "We should end Welfare as we know it", and "The era of big government is over". He signed the DOMA that year, and also received FOP police endorsements for his tough on crime stances.
Everything I just described is now considered "racist", "homophobic" and "intolerant" by the left of today's Democratic Party.
I think the problem that has liberals in meltdown right now is that America didn't vote for their vision. They made Donald Trump out as "deplorable, racist, sexist, homophobic, misogynistic, ect....and America responded by electing him with over 300 electoral votes.
That means either A.) American's didn't buy into the Democratic logic or B.) Americans didn't care.
Either way, it's an agonizing defeat for liberals and they don't know how to deal with that.
What's being talked about here goes back much further than 20 years. What used to be called the 'New Left' had its start in the fifties and sixties. They demonstrated outside the 1968 DNC when they didn't get the candidate they wanted. By 1972 New Left ideas had captured the imagination of the wider left and they got the candidate they wanted. Both times they helped Richard Nixon to win. The ideology was not popular and caused them to lose elections so it had to be toned down, in public at least. This message was further hammered home by the election losses in 1980, 1984, 1988 and 1994.
However whilst New left ideology was losing elections it was still gaining ground. Although, just like soviet communism, its advocates think they are fighting for the interests of 'the oppressed' in reality the interests they represent are those of the bureaucratic class, again just like Soviet communism.
So whilst the New Left were losing election after election, causing the Democratic Party to disguise this aspect of its ideology in elections like 1996, its supporters and adherents in the bureaucratic class - in government, in academia, in big corporations, in schools and in the charity/non profit sectors - were doing everything they could to promote and indeed enforce this ideology. This is what became known as political correctness and it was in full swing well before the 1996 election.