It is easy to understand that the requirement of sports photographers for carrying their long lenses dictates a grippable handle instead of a low-profile tripod mount. However, these concerns needn't be mutually exclusive. All it takes is to design the rotating collar generously wide, and let it have a broad and sturdy foundation for either a handle-type foot, or a low-profile massive foot suitable for long exposures. Surely it'll add mass, but even an increase of 2-300 grammes for a better support wouldn't hurt the sports shooters by much, and if judiciously engineered would make wonders for everybody else.
The current approach is contrary to these goals, though. The collar has been narrowed in general, and the foundation for mounting the tripod extension ("foot") has been weakened by paring it down in mass and size. From what I see of Canon long lenses, they are not much better designed than the corresponding Nikkors. Thus we apparently face an industrial problem.