Except my first handgun, all of my Revolvers are stainless. I have several stainless autos as well.
However, the main reasons get into material interactions, lubricity and machining. Stainless is more prone to galling, especially stainless on stainless, so it's use in the slide rails resulted in a less durable and less reliable firearm, long term. Stainless, in the presence of air, creates its own passive, anti-corrosion surface. When that surface rubs on another surface, the corrosion layer is removed, and is actually abrasive. Sure, there are alloys that mitigate this issue to some extent, but the cost is very high. So too, stainless, until recently, was harder to apply a harder, high lubricity coating to. It is still harder to do, but relatively recent advancements in coating technologies have narrowed that gap. In addition, stainless with aluminum has some corrosion cell issues that prevent direct contact, and then the whole galling corrosion layer issue is even worse. The new coatings for stainless and embedded metal (with very hard coatings or treatments) in polymer frames has opened the window of reliability and wear considerably, which is why we are seeing an increase in stainless slides in autos.
With a revolver, there are no high wear surfaces of stainless on stainless, and the cycles put on revolvers is also significantly less over a given lifespan than on an auto.