I don’t think so really, I mean you are not always going to please everyone, with the 7E7 you would undoubtedly upset some of the majors (particulalry US majors) if you had Trents only.

Personally I think that if a manufacturer wants to restrict the number of engines through exclusitivity deals (and therefore make money from the engine manufacturer) then they need to still offer two options.

It just happens to be that the exclusitivity on the 777 was the wrong option for the aircraft based on the target market airlines.