When I was working in healthcare statistics, we placed substantial importance on what was called the underlying cause of an injury or disease.
The injury might have been a blow to the head, resulting in a laceration and bruising. What caused the blow to the head? The person fell and hit their head on a table. What caused the person to fall? They tripped. So the underlying cause was "tripped and fell".
Mark Zuckerberg thinks real names lead to better behavior online, but he fails to follow up with the underlying cause; he sees a laceration and bruising and doesn't investigate how the patient got the condition.
Real names don't inherently lead to better behavior online. /Consequences/ lead to better behavior online. Real names are simply a way of attaching consequences to individuals.
But many people don't believe that consequences will attach to their names (see Brock Turner), or don't care.
What platforms - especially Facebook and Twitter - are incredibly slow to realize is that the consequence that most of the bad actors care about the most isn't having their actions online associated with their identity offline; for a lot of these people there's no distinction!
The consequence that most of the bad actors care about is /loss of platform/.
Telling people "if you don't behave, you're not allowed here anymore" is much better at inspiring good behavior than any real-name policy.
TLDR: to most online bad actors, "I'll tell your mom!" is a MUCH less important factor in controlling behavior than "I can push a button and take away ALL your content and influence".
