I don't think that makes much financial sense. The risk of alienating existing users --which they obviously took-- far outweighs the benefit of obsoleting existing supplemental materials.
You don't think the design team did a solid job, or you don't like the direction they took with their design? Personally, I think 4e is close to, if not the best designed D&D core rule set --which doesn't neccessarily mean I think it's the best game... 4e is still the new shiny for me, and a thorough evaluation of it is going to take time. But I also understand that a segment of the fanbase really dislikes the overall direction they took.
Also, marketers drive nothing.
You run the risk of defining 'the good of the hobby' as 'what I personally like' with statements like that.