And chopping your balls off prevents pregnancy. It works, but it's a draconian solution, there are better ways. Eliminating player trading to prevent 'gold sellers' is about as lazy as you can get.
It helps to understand how gold selling works. Gold sellers rarely get their currency by honest means, they usually either hack the game itself or hack peoples accounts to steal assets. Preventing these actions should be done regardless. The other thing needed is enough interest in the game to justify the time effort and risks associated with gold selling, and Elite simply doesn't have a large enough player base. Furthermore gold sellers thrive mostly in asian countries due to a difference in tolerance for microtransaction models and P2W, and generally stick to games that are microtransaction heavy because it means that
1: the players are used to spending real money for in game items
2: there is a market to undercut.
As it stands, if there was enough interest in gold selling in Elite it would already be happening, as demonstrated above. Hypothetically, if I were a gold seller, I could easily arrange to give credits to someone, it would simply take a bit of time to complete the transaction but in a couple hours a new player could have 100 mil or more. Would it be the most ideal way to do it? No, but it is entirely possible and yet it does not happen.
A condom might not be the most fool proof method of preventing pregnancy, and accidents can occur, but it is infinitely preferable to chopping your balls off. I.e. there are better ways....