Same could be said about a concept of solo traders. If you are as successful as you claim why don't you run a fund? However, a lot of people do solo trading as its more of job/hobby where the only thing you risk is your capital. Plenty of people don't have stomach to deal with others lifetime savings? (or even potential of such person in your client pool)

Its different. Not everything scales as nicely and dealing with responsibility is going to become a burden soon. Here you are selling your advice, most likely all traders have similar access to this advice and can perform trades with their own judgement.