If they are scam I think they should be ban from market and only KYC projects should be allow to get promoted, if some scammers promote their projects in market the indicators should report it to the forum, and good projects should be promoted because they gives good and profitable future to the investors so I think it is good to promote them.
What do you mean by ban from the market? Nobody can do that in the internet. We can make people aware but this is not a regulated place to ban someone. There is nothing like "Internet police" to check which business should be banned and which one not. That is a bad thing about decentralization though. Scammers will always try to take advantage of this.
Promotion of good projects is another thing but talking about scams, one should check the reputation of the site before they visit and decide to play with their money.