Reddit is pretty much a case study of upbringing without effective punishment. In real life kids behave because they have skin in the game—if they misbehave, they are not allowed ice cream. On the contrary, if you are banned from reddit, you can simply reset your browser and create a new account.
I doubt you can fix reddit with a smarter design, because that won’t change the troublemakers. To fix reddit, you would possibly have to profoundly change the way our civilization socializes the young, remove inequality and provide more psychological support. Or you would have to build a better reputation system and use that for sorting, but that’s likely going to be incompatible with anonymity and it won’t be as fun.
I doubt you can fix reddit with a smarter design, because that won’t change the troublemakers. To fix reddit, you would possibly have to profoundly change the way our civilization socializes the young, remove inequality and provide more psychological support. Or you would have to build a better reputation system and use that for sorting, but that’s likely going to be incompatible with anonymity and it won’t be as fun.