Actually, I think it is. More so than for any other cycling discipline I can think of.
I’m not saying you have to spend hundreds or thousands on custom build, with classy Californian components though. A sensible set-up that you’re confident on, and that doesn’t limit your game doesn’t have to cost much, and can hugely improve your performance.
It’s because polo is still new and as yet relatively unserved by mainstream manufacturers, that having a set-up that works well can maximise your strengths and minimise your weaknesses more completely than in other disciplines. In MTB, road, TT etc etc, the designs are pretty well evolved, and the regulations so tight, that nobody can get much of an advantage by getting the next best thing.
The pendulum has swung to the extremes of shortness and tightness in terms of frame geometry, dual brakes are getting better and better and in some cases are being replaced by single front brakes, fixed is (practically) dead and I can’t wait to see the next developments.
I’m probably being spectacularly short-sighted, but I think that most of the big innovations have been and gone, and there will follow a period of consolidation and standardisation. That’s not a bad thing, necessarily, and it will help to mature the sport, but I have to say that these last few years of wacky ideas and trends have been great to be a part of, and hopefully some genius will prove me wrong with a radical triple-brake system, 700c/24″ wheel combo or other craziness.