For the same reasons presented at Tatiana Estévez’s answer to Why does Quora delete all questions pertaining to the ban of Quora users?
It would be seen by Quora as violating BNBR, and it would be seen by Quora as embarrassing to writers. The scenario brought up recurrently by Quora moderators is the writer going for a job interview, and the prospective employers having Googled ahead the writer’s activity on Quora.