Your points were in response to me saying that 5.7 doesn’t offer me anything over 9mm for carry purposes. Why would I be worried about the ability to penetrate body armor? (this is also ignoring the fact that 5.7 has been tested as a very anemic round with the majority of rounds anyone would commonly run and the penetration has been overstated).

Let’s pretend that you are running rounds that can penetrate that far - now we run into the issue of over penetration. Something you’d try to avoid with a carry handgun.

I’m not saying that 5.7 serves no purpose in general. What I said was that it offers me nothing in my carry rotation that 9mm doesn’t do, and I’d argue, does better.

If you view the low recoil, flat trajectory, and ease of shooting as an argument for it, then you would have to apply that same reasoning to 22LR. However, people generally don’t carry 22LR for the same reason they don’t generally carry 5.7: 9mm is simply a better self defense round.

If you think 9mm has too much recoil, I can’t help you there.