I used to brew beer as a hobby. Had two six-gallon carboys going at one time. I did a lot of IPA. I find breweries continue to over-hop it for my tastes.
Originaly, it was brewed with ale yeast because the higher fermentation temps allowed the casks to ferment while on Brittish ships headed to India, and the subsequent overland routes once there. (It's a hot place) The extra hopping done post fermentation assisted with the flavor- or masking the flavor, since shaking wort is a bad thing to do while fermenting.
As I recall, ale yeast requires something around 75F, while lager is around 45F. The "India" part of the IPA denotes the extra hops. Plenty of ales around with less.