In the aggregate sense, it eventually netted out. But a lot of people who sold when it looked like prices were collapsing sure got a pretty decent chunk of their bank accounts "erased".

Panic sellers always have that problem tho, regardless of the source of panic

I fail to see that anything or anyone could be blamed besides themselves. We cannot have the net to be emotional support for investors.

For a market to move, people need to buy and sell. So while value might not be erased on a global scale if the market recovers to the original position, lots of people will lose (and gain) large amounts of money.

That's not true. Many people have auto-sell / buy triggers set up when something drops below a value.

I don't know about many. I don't know of any retail investors that do, and if I did I would have guessed that they'd be buying when prices drop, not selling.

Parent did say “sell / buy” (perhaps they ninja edited). A limit buy order is a basic tool of retail investors (like me :) ) and may have been what parent was thinking of. That said, I don’t agree with parent or great grandparent that the destructive impact is large.