It's been a few years since I've retired, so hopefully anyone I worked with has forgotten me, so I'll comment on my early retirement. (If you recognize me, hi!)
I retired a few years ago at 55. This was greatly facilitated by being able to move to Malaysia via their TalentCorp program that my wife qualified for, as she's a Malaysian citizen (which also got me a PR). There are many reasons I like being here, and for retirement reasons one of the biggest is super cheap health care, even if you go to private hospital and pay out of pocket. I qualify for gov't healthcare, so if I don't want to pay, it's super cheap to use a gov't hospital.
I'm always impressed how many posters here are managing their funds, doing planning, etc. We only have 401k's and they are managed so we don't have to do reporting stuff for my wife (who was a MD at a financial firm in SF). My wife's income, plus me finally deciding to take a job where I'll really get paid put us in a position to say 'fuck it' and move in Feb 2023. Selling a house in the SF Bay Area didn't hurt either. I came to the realization that I was done with working after my mom died in 2021, after a short battle with cancer. We have no kids, and the only family I have left in the US is my brother.
Our forecasting is a simple spreadsheet, with a few variables, all using present-value for stuff (we're just assuming that all of our gains will match inflation, and that's it). FX risk is probably my biggest really-long range concern. I have enough assets in Malaysia now to mange things for a while, but big swings in the exchange rate just leave us with less cash in 13 years when I turn 70 and start withdrawing 401k. But stuff is cheap enough here, we could certainly live on small income if needed. ($1k-$2k/month)
For those interested in retiring here, Malaysia has fixed their MM2H program a bit (Malaysia My 2nd Home), it just requires a $150k deposit and buying property worth at least $140k. (and you can take up to half the deposit to pay for the property, medical, or tourism in Malaysia). Probably not the best program if you really wouldn't be able to return to your home, as it is a renewable pass and not a PR (unless you drop $1MM into the account).