Re: Why no swing out cylinder single actions.
I'd guess nostalgia is a big reason why traditional single actions are how they are. Both Colt and S&W did offer SA only revolvers with swing out cylinders for bullseye shooters. They, I would assume, were unpopular, or they would still be produced.
Really, in the modern DA revolver, there is no downside. Shoot it SA if you desire, and take advantage of the usually crisp SA trigger pull they offer, and still have the option of DA fire for self defense practice.
Kind of a solution looking for a problem.
Personal opinion is a good thing, and everyone is entitled to one. The hard part is separating informed opinion from someone who is just blowing hot air....