Comparing malfunctions in revolvers and semiautomatics isn't really "fair"; they are different kinds of machines.
The semiautomatic pistol relies on "outside forces" for it to function properly: it needs the ammo to be shaped properly, the powder charge to be within a fairly narrow window, the shooter to grip it properly, a magazine (which is only "sort of" part of the pistol) to work properly, and probably some other things that I'm not thinking of. If any of those things goes wrong, even though it isn't the pistol's "fault", it's a malfunction.
With a revolver, misshapen ammo bad enough to cause a malfunction won't be put in the cylinder in the first place. It has to have pretty much a zero powder charge or a huge one to cause a problem. It doesn't care how you grip it, the magazine is basically your fingers and eyes. And so on and so forth.
Here's an example. If a round has a defective primer, it causes a "malfunction" in a semiautomatic pistol. In a revolver, you just squeeze the trigger again and shoot the next round.
I have a Russian Makarov that I've owned since 1988 that has never once malfunctioned. But it will, if I stick a bad piece of ammo in it, or limp wrist it badly enough, or use a poor quality magazine, or whatever. An equivalent single-action pistol will probably never malfunction until one of its parts breaks.
And I literally don't mean that revolvers are better. They are just a different kind of machine. They are slower to reload, and as I said, they rely on your eyes and fingers to be the magazine. Their capacity for a similarly-sized handgun is lower. Inherently, as machines, they are probably no more or less likely to malfunction than a semiautomatic pistol. However, since the semiautomatic relies on "outside factors" for it to function properly, it will probably "malfunction" more often. If someone is meticulous about their ammo, grips, magazines, etc, they won't experience these "externally-influenced" malfunctions. Thus they will disagree with someone like me, who shoves cheap range ammo into the after-market magazine and then grips the pistol haphazardly.