Instead of cultivating the pub, the owners demanded that the visitors be safe, boring and obedient witers of value. This killed the pub and with it the business.
The most visible aspect was the duplicate close. Duplicate closes scare away fresh patrons, blocking precisely the path that old timers took when they joined. And duplicates allow anyone with a grudge to take revenge. After all, there are no new questions, and you will always find a duplicate if you want to.
To create a new Stack Overlflow, create a pub where programmers enjoy drinking a virtual beer, and the value will appear by itself.