Even then it is unlikely anyone is going to lose 200%. Margin calls tend to take care of that fairly quickly.
I have had one margin call, and I actually ended up making money on the matter; and the trade itself was a very small proportion of my net.
I also have a friend who was (and still is) day trading options. He got greedy and got caught sideways when Boeing went boing and lost something like 20k in a couple of minutes. Didn’t wipe him out, but he pulled in his horns for about 6 months licking his wounds; he is a bit more cautious now.
Major adverse excursions normally occur to people who are either blinded by greed and are betting the farm, or people who put all their eggs into one basket and forget to watch the basket.
Successful traders - the folks who have become rich by trading - pretty much follow a rule that they never risk more than 1% of their net, if that, on any trade. They also limit the number of trades on at any given time. My friend who got boinged was well over the 1% limit. He got “cute” and forgot about the rule about trying to catch a falling knife. He was, however, trading an account far separated from his retirement portfolio; had he lost it all, he would have lost his “play money”.