I see the same thing happening on the other side of the aisle as well... old blue dog democrats are feeling more and more like outsiders to their own party... centrist D's and R's (who clearly still make up the majority of both parties) are being ignored and left without a voice while the extreme left and right scream and shout and raise hell about minutia as often as they concern themselves with anything that actually matters..
I read an article earlier this week that spoke to the "Bernie Sanders Effect".. where despite him losing handedly to Clinton in 2016 in the D primaries (all while serving as an independent and a declared socialist), that he gained enough public air time to influence and impact the D party and that he is largely causal for the huge shift over a relatively short period of time within the D party... essentially without Sanders there would be no fixation on "the squad" or any desire to appease them, no one would pay any attention to the "green new deal" or any of the outrageous DEI crap that is now in the center of D discussions and legislation attempts... but now that these clowns are all in office and the younger generations are listening to them, the D party doesnt have much of a choice but to play to their whims, or they lose more centrist seats to more people that are following in comrade bernies footsteps..