One of the most infamous is/was New York City's SOTA program [1], which attempted to relocate and provide one year's rent for people from NYC's shelters. They basically shipped families and individuals out of state to other cities, hoping they'd find a job and affordable housing there. NYC is an economic powerhouse if you're credentialed and high enough on the treadmill to make it work, but not an area you want to start out with nothing; you can imagine that someone had the bright idea that there are cheap houses and entry-level manufacturing jobs in other growing cities, someone homeless and jobless might have a better chance of integrating into society than panhandling on Wall St.
The program met with outrage from the destination cities whenever anyone (utterly broke, with a history of homelessness, with no local family or connections...the program worked for some but did not for others) ended up in trouble and the locals found out they'd come from NYC. Turns out a lot of people would rather have their bright and bustling new-money "innovation hubs" and "tech corridors" unsullied by undesirables from dying cities.
It's one thing to turn a saloon and general store into a quaint Old West ghost town when the gold mine runs out. It's another to turn dying cities that once had populations of millions working in bustling industries of rail, coal, steel, or automotive manufacturing (like Bessemer, named after the inventor of the Bessemer steel converter, or other cities like St Louis, Detroit, Cleveland, Gary, Flint, Dayton, etc.) into not just the current Rust Belt cities but an enormous ghost metropolis.
A good first step is a country wide housing, healthcare, food, and job guarantee. If bezos zuck musk gates etc can be billionaires we can provide a minimal standard of living for everyone. I'm open to considering any research that says doing so is impossible, but I doubt any such research exists.
Subsidize 2 luggages and a 1-way bus ticket per household member, to anyone that wants to move to a new location. No questions asked. You can do it X amount of times in your life, and anyone with income below (a multiple of poverty rate here) qualifies. That's it.