And most such sites make the assumption that forward returns in future are going to be like those in the past, implicitly concluding that portfolio returns are uncorrelated with starting valuation levels. It was not just luck that made SWR approaches starting in 1982 work so much better than the ones starting in 2000.

I'm sure you're aware the 4% swr is the *highest* rate for an 80/20 or 60/40 portfolio to last 30 years based on all historic starting dates.

Yes, that's not to say a new worst starting date can't happen. But, 4% is a good starting point if you're an average joe trying to spend down a portfolio.

And historically, using a 4% rate you're likely to end up with 5x your starting portfolio even after 30 years of withdrawals.

Why?

Again, because 4% is the *highest* "safest" rate. You could've withdrawn say 6%, but you didn't know that, because you couldn't know that, because no one knows how the future will unfold. The S&P 500 earnings yield might be an indicator though.

Anyways, I know the Bogleheads like to say use a 2% rate or whatever because it will last forever but then you risk not enjoying your money. But I guess your heirs will?