Their stance towards refugees and immigration are extreme, it's a white nationalist and isolationist approach for a country which was built on immigration. Trump is our President. AOC couldn't even get Bernie or Warren to be competitive. The right has moved just as much as the left. The white nationalism is a major problem.
There is no question a radical element of the right wing. Anyone denying there isn't a bunch of white people who hate all ethnicities is kidding themselves.
But that position is not strongly represented in the current party. Controlling your borders is not racist. Hispanic Americans support this almost 50%. To me this is a terrible talking point for the left and a main reason why Hispanic support for trump is very high.
AOC got every democratic candidate to decriminalization illegal immigration, support Medicare 4 all and some type of expansion of traditional welfare systems.
It is not comparable from my biased eyes. The radicalization of the left has far outpaced the right.