gHahaha .. Really funny! Canon is 2 axes and hybrid af in 100mm L IS macro stabilizes movement in 4 axes. Olympus IBIS is 5 axes. ;-)
You are certainly correct regarding optical stabilizers. Having a stabilizer in the camera body will obviously lead to at least some optimization limitations as the vendor cannot fully optimize for specialized lenses (for example for big whites) and in addition it kills off any opportunity to come out with something like the 100mm L macro's IS system.
I am looking forward to a mirrorless FF-body - maybe sony a9r - with 5 axes in-body is, so i dint't have to buy in-lens is in a 24/2.8 or 28/2.8. and when a big white with in-lens is is attached, the ibis will automatically be switched off. In one word: Best of all worlds. :-)
I don't see axis counting as any feasible way of comparison here. It must be obvious that from a development standpoint a vendor will run into limitations trying to cater to a broad selection of lens usage scenarios or do you really believe that at Olympus they work miracles instead of engineering?