It absolutely has a lot to do with Right wing/Republican propaganda, California, Chicago, and New York represent everything they hate so they constantly use both states and that city as negative talking points.
One point they constantly make is that New York City is a crime riddled hellhole, meanwhile NYC has one of the lowest crime rates in the entire country, and one of the lowest murder rates, it’s just a massive city with a massive population and everyone there has cameras so when stuff happens it goes viral. Also the Red States tend to have much higher crime and murder rates.
All in all this is usual conservative/right wing tactics, they constantly want to isolate and segregate themselves from other ideas, and aren’t afraid to take over where other people live to exclude the people already living there. This is why Idaho, Texas, Florida, and Utah have similar campaigns about “don’t California my state” and by “California” they mean don’t bring your “liberal/socialist/Communist/woke/progressive/democratic” outlook to their states, because they don’t want to be responsible for cleaning up the racism and various other problems that the red states seem to have adopted as their identities.
Also I know quite a few conservative Californians and New Yorkers that recently moved to Texas and Florida, and as conservative as they thought they were they actually talk about moving back to where they came from because of how it is in their new states, except for the fact that they moved to the new states because they can afford so much more than what they could in California.
Overall my point is, if you consume right wing media then you are conditioned to hate blue states, and particularly those blue states are Cali, NY, and the city of Chicago as well as DC, I’m not saying these places are without flaws, but I am saying that the propaganda and disinformation about those places has amplified the hate towards those places and their residents.