I suppose all of the specific anti-California sentiment stems from Californians having higher incomes relative to other states, on average, and thus being more likely to relocate than are those from other states.

But I still don’t really understand what they mean? Are they talking about specific cultural things unique to California? If so, what? And from where in California? The state is massive, with many different cultures based on location, race, ethnicity, working conditions, hobbies, etc. (San Diego is very different than Los Angeles is very different than San Francisco is very different than Sacramento... Even surf culture differs considerably across those areas.)

I’m guessing what they’re really trying to say is that they don’t want the high cost-of-living (and burdens it brings) to come to them? But that has nothing to do with Californians and everything to do with the given State’s local leaders and economy.

This captures a good number of the stereotypes: https://www.youtube.com/watch?v=nlLcBQPQ96Q

Today I saw a bumper sticker, “Dont California my Colorado”. In other words, don’t move to Colorado from California.

That is not at all the spirit of that bumper sticker. It is saying if moving to Colorado from California then don’t bring California with you. More specifically: please adapt to the destination instead of trying to convert it into the thing you are so willing to abandon.

Of course people assume that everyone who moves to Colorado from California is going to being California with them, so it's the same thing really.

It’s only the same thing if you are from California AND are too self-consumed to tell the difference. I promise the sentiment is commonly known in every mountain, Midwest, and fly over state.

What's old is new again. These stickers were printed 30 years ago too when there was a huge influx of Californians to Colorado. Source: told about it 10 years ago by native Boulderites

In the mid-90s there was a huge influx to Colorado from California. I never saw this bumper sticker. Closest I saw was the common “NATIVE” sticker.

One saw DON'T CALIFORNICATE COLORADO stickers in Colorado in the 1970s.

35 years ago I saw bumper stickers reading "Don't Californicate Oregon". Some things never change.. I suppose if bumper stickers were a thing at the time (1960s, early 70s ) & the locals were more aware of the consequences of selling their orchards to the developers there might have been bumper stickers reading "get your East-coast butts out of our valley"... but it seems lucre lessens many insults.

Or if you do, don't try to make it work like California (either socially or politically).

Ask older New Mexicans what they think of Coloradans and Texans.

I can imagine overhearing a conversation where someone says they moved here to escape the west coast wildfires in some brewery tap room in Colorado...