You have e.g. lifelong New Yorkers who may have gone to school elsewhere but can't really imagine living anyplace else.
But you have a couple of different groups broadly speaking. People who never moved out of a small town and people who gravitated back towards some major metro for any number of reasons.
And remember there are a lot of basically "small towns" that are counted with urban areas in the US.
Sometimes those small town groups move together as well!
My example: Shortly after college, I moved to the city half way across the country because my high school friend lived there. And then several other of our high school friends (all from a small town) moved there with their spouses as well, and we'd all hang out and even started a company together for a while. We eventually all went our separate ways, at least as far as what states we live in. (There is still some amount of moving to be closer again going on as well. For example my ex's family and a friend from the state we moved to moved closer to her.)
When I used to live in Massachusetts I found it boggling how many people had never lived anywhere else. Southern California, where I now live, I think actually has a narrow transplant majority.
Which is fascinating, because while we know California is technically net-outward migration (people moving to other states), the demographic of people net MOVING to California is by people in the top 5%.
California is essentially gentrifying at the state level with wealthy transplants, pushing working and middle class people who grew up here out of the state.
You can't win, huh? Move to California, you're gentrifying it. Move out of California, you're gentrifying wherever you go. Perhaps this framework isn't the best to think about it.
I think you’re falling into an easy trap when it comes to the word “gentrification”
No individual, be it in a state or a city or neighborhood, is to blame for gentrification. By definition gentrification is a collective movement — one billionaire with a ski chalet on a private mountain in extremely rural Montana does not gentrify the entire region, nor does it really raise the property values of any home near it.
Gentrification is systemic, and approaching California’s population loss and gain through this framework explains pretty much everything that is wrong with California at a policy and macro level.
The reason for this “gentrification” at the state level would confirm everyone’s priors: the cost of living is simply too high for most people. That would be greatly alleviated by building more housing to increase the supply for the bottom 90% of people who struggle with their mortgage payments, rent, or scraping enough money for a down payment together and realizing they can buy a home outright twice the size in Texas for what is just the down payment in California.
I find Massachusetts to be pretty big, for a small place. I moved here from Maine after college and there isn't really anywhere else I want to be. I travel recreationally, but like--if I'd been born here, I don't know why I'd live somewhere else. (Spent time in California, for example. Not my thing.)
Sometimes I think about buying a place back near where I grew up, but my parents don't live there anymore and it's really not that much cheaper than my current house for losing out on a lot of things, so...I don't know why I actually would. It's just more lawn-mowing.
I have no data, but the communities I have found in Houston are also very, very heavily comprised of out of state transplants.
Rural Texans who left home to seek their fortune are said to favor Dallas/Fort Worth more than here, and that feels fairly true, but again: no data. I know more people from out of state (or other countries) than I do from elsewhere in Texas.
I think this is a big part of why I believed 6 in 10 to such a massive number -- I grew up in southern California and then moved to the Bay, and it feels like most people I knew either had parents who immigrated before they were born or they themselves moved to the area for school or work.
