I disagree that a MUSH wouldn't work for Traveller. It all depends on how it's handled. One could easily run a MUSH where there was no actual interactive, real-time space code, and instead do it all by adjudication. That way, the problems with time and communication wouldn't matter. It would be staff-instensive, but all good MU* are. Any coding systems should be there to enhance and guide RP, not dictate.
As for profit, if such a MU* were stood up, I doubt very much that there would be a large player base, as the vast majority of MU*s are free.