[tuberelay]

Dow dropped 90% in great depression, so even trading the dow with 10% leverage would've wiped you out.

Dow also dropped >50% in GFC, so 2x leverage would've ended you.

Taking ultra risky bets when you are young is sensible because it isn't actually risky. This is because for a 30yo with good career prospects, your future career is probably worth an amortized $5 million dollars. If you have $200k in savings, that is only 4% of your true net worth. If you lose it, you still really have $5 million dollars. Therefore playing loose with it is pretty reasonable.

If you're 63 and will retire in 2 years, your amortized future career earnings are probably $200k and your assets $5million, and then you should be conservative.