live in a submarine for years, so you can live in a cave the rest of your life. but wait, you won't be trapped in the cave. in fact, you'll be obliged to expose yourself to the surface frequently, because you're dependent on life-support systems that must be fed with external air and materials sourced from mines. it's certainly possible, but everyone who doesn't die in industrial accidents will die of cancer. not to mention that musk will lose interest and cut communications and pretend it never happened after a year.
United States