Selling Legendary Rank bitcointalk account is not prohibited but heavily frowned upon, as per the rules mentioned by DdmrDdmr's post.
Yes, account sellings and buyings are allowed, but they are discouraged. It means people don't like bought accounts, because those ones can be used for shady intention, such as creating threads of scam projects in order to increase level of credibility with high rank accounts. Addtionally, it is easily to trap newbies to accept deals of exchange by using high rank accounts. In fact, there are no one buy low rank accounts, and it is a point.
Moreover, with merit system, now high rank account without single earned merit looks less valuable, in my opinion. Because a newbie or junior member with a single or bunches of merits is more interesting than a Hero or Legendary member without one earned merit.
Buying and Selling bitcointalk accounts would only make the buyer and seller lazy enough to achieve the rank personally rather than buying an account that the result can cause a spam in the forum which I did notice that some Legendary rank account is spamming in this forum. I am sure that some of you guys did notice a legendary rank that only post spam. (Not All Legendary Rank, only the legendary rank account that has been sold and bought).
This is one of main reasons why we have a magical merit system.
