I am 190cm tall and I feel like 27.5/650b still fits me better, I am not exactly short.
Again, I have both, love both. The bikes are very different in geometry, intended use/feel and are each designed to take full advantage of their respective tire sizes.
agree that 29" wheels are simply more efficient when rolling and focusing on the maintenance of moment. Around tight turns and tight courses which involve lots of acceleration/braking, 27.5 would be the way to go.
Interesting comparison between me and a friend ripping some doubletrack (he was on a 26" GT rigid alum hardtail, I was on my 29" carbon hardtail w/ front air fork...)
The 26" bike clearly had superior responses during acceleration/braking which didn't seem to involve much penalty while holding that momentum. 29er obviously tackles rough terrain a bit smoother but hard to say how much better since the bike was rigid vs air fork. 26" geometry liked to change direction faster. Otherwise both bikes seemed about equal in outright speed with the 29er air fork possessing clear advantages over the nasty terrain.