I am pretty amazed by the fact that hosted forum solutions are not thriving. As everyone knows, making money out of a forum is not easy anymore. It is almost close to impossible if you do not do the right things which need investment.
I have heard of a few MyBB based forum solutions where you get everything free and platform put their ads. If such a model succeeds, people can ask for a share of that revenue. Instead, such services are mostly used by kids who want to start a forum with no idea.