Gun writers have been rehashing this tired old question for many, many years. It is one of those stories that is dredged up again and again, possibly when the store of other ideas runs low and they need something to fill the empty spaces on pages 43 and 86-87. The example below, from the year 2010, is a clear and well reasoned example of the type. However, it supplies no conclusion you could not have read in 1910. The startling conclusion: ". . .the old cliché seems to fit. It's better than nothing."
I have a few thoughts on the subject. (Mine are not all that original either.) Reliability of the .22 LR cartridge is not good. Ignition failures are commonplace. The above article looks at CCI cartridges, which are better than most in that regard, and far, far better than some other brands. Still, reliability is rather lackluster even in the better brands of rimfire cartridges, far behind what you expect from centerfire ammo.
So I suggest manually operated firearms if you insist on trusting .22 LR for defense. A revolver seems to me a better idea than an auto pistol, and there have been some mighty slick and quick pump-action .22 rifles made over the years. A failure to fire is more easily dealt with if you, not the cartridge, are responsible for cycling the weapon. The drill in case of a failure to fire works just about the same as continuing to fire normally.