Just thought it's a great idea easy to get going after a puncture surprise others don't copy it .
Frame rigidity combined with light weight could be a problem for sports bikes, particularly at the back.
Cars have stub axles, but weight is not such a consideration.
Cannondale have their Lefty fork, but that's only fitted to hybrids and MTBs, and only at the front.
Development budgets for bikes are tiny, and cyclists are notoriously conservative - any innovation is roundly slagged off on the forums.
Thus the money and motivation to design a stub axle bike frame is just not there.
Some motorbikes now have stub axles at the rear, but not at the front - unless
@keithmac can tell us differently.
I'm sure he posted something about rear wheel removal on such bikes not always being easy, so presumably the engineering justification lies elsewhere.