Got a bit of time and a keyboard to give a better response. This isn't a direct response to the OP, more in general on the topic itself.
To me, retiring abroad for lower cost of living comes to mind when someone has less than $100k in savings, no home, no pension, no kids to move in with (or anchor to the US for), and a modest social security is going to be their only income in retirement. It's a last ditch effort to stretch minimal assets through the golden years. If that's the case, then sure, go for the cheapest possible place while trying to find somewhere that at least has decent medical care. I'd first and foremost look at US territories, Puerto Rico immediately coming to mind.
Otherwise, there's a lot of places within the US that are still pretty cheap. Housing is the #1 cost in retirement, closely followed by medical care (health depending). While many zip codes are in the half mil for a 3/2 home in the burbs, there's a lot still in the low $100s if you want rural life, especially in the deep south or the middle America prairie. Shit, I'm going to put my house on the edge of the Black Hills up for sale later this year for about $200k. National average of $450k and going up? That's because of shitty cities like LA and Denver with overrated home values. Don't live there, live rural.
But one thing that I would never do, ever, is give up my guns. My ex moved my kids to Maryland, I lived close to three hours away in Virginia because I'll be damned if I'm going to deal with permits, restricted carry and transportation, and semi auto restrictions. That was just one state to another, much less than going to another country that outright bans ownership for anyone other than the state. Going to another nation? Hell the fuck no.
I had men of 14 different nationalities working for me at one point, Europeans, Africans, Asians, S. Americans. All of them were stunned what freedoms we had when it came to firearms. The entire rest of the Bill of Rights was completely foreign to them. I had some working for me that were wanted in their home country from when the communists took over and were hunting for anyone who worked against them previously (Nepalese). I had Indians that still dealt with the caste system and had relatives in outright slavery, they were just trying to save enough to buy their sister back into the family. Then there were the Fijians who were trying to save enough to get a well of their own so their wife and kids didn't have to travel two miles to get water every day.
Cheap countries are poor countries, dirt fucking poor. There's no medical infrastructure, no power grid that doesn't involve a rat's nest of wires coming out of every power drop, high crime, shitty roads, and cops hustling you at every checkpoint if they think you have three dollars in your pocket.
I'll be bagging groceries and flipping burgers at 94 to make ends meet before I think about leaving my country for a lower cost of living retirement. Instead, I'm saving my money, working a career with a good pension at the end, and paying off the house as fast as I can to not have a single bit of debt within a decade of my retirement date so the wife and I can have our nice retirement on 40 paid in full acres and a house that will last well beyond our years.
