I don't think I'd borrow fiat. I get why one would do this, it's tax efficient. But I don't like the idea of perpetuating the fiat game, nor giving custody of my coins to some entity who can rug me.

If / when Bitcoin reaches a bajillion cuckbucks, I suppose I'd stop working as much as I do currently. I'd slowly sell off my stack to pay expenses, and leave the remainder for my kids. If nobody works, the stack dwindles to zero, as it should do in any fair system.

No yeild hunting silliness, no retiring forever and ever off of the backs of others like the FIRE guys dream of with their 4% rule. Save money, spend money.