It only bankrupts idiots like those on /r/wallstreetbets or those who put all their money into one stock. Yes the market may go down, and it may go down a lot, but that’s not going to make you bankrupt unless you make extremely dumb choices.

Luckily most retirement plans come with a target date fund, which is an easy way to diversify and get basically guaranteed gains.

Also, it’s the only retirement the middle class has, so you can’t destroy it.