Bullet design, caliber, fps all have a LOT to do with performance.
For example, until the 1980s, the 158gr LRN 38 Special was the most issued cop cartridge. This was/is a fairly soft bullet, and had a terrible track record of over penetration on flesh and fail to penetrate everything else. It got many cops/bystanders hurt. I was surprised how much the 126gr era's gone bullet resembled that bullet. Maybe that explains the penetration.
In revolvers the best one shot stop cartridge was the 357 mag, with Federal 125gr JHP. It had everyone chasing their tail.
The 9mm with 115gr bullet was pretty sad, especially if FMJ variety. I worked with old timers who insisted on fmj loads, mostly former military. I asked to be their beneficiary. The 147gr was NEVER intended to be a duty round; hype over its use by military spec ops got more good guys hurt.
The 9mm was pulled by most departments after the famous Miami Shootout, the 10mm, 40 S&W, 357 Sig all attempted to improve one shot stops. Most did, with the right bullet.
I can tell you the 40S&W FMJ is a joke.
Now comes the Hornady Critical Duty 9mm load with 124gr Flexlock bullet at 1175fps. This bullet design, plus weight, and velocity, is what allowed it to pass ALL of the FBI protocols for a sidearm cartridge, the 1st bullet to Ever do that. Many departments are switching back to the 9mm simply because of the Bullet, not the cartridge.
So, it's not just caliber, its not just velocity, its not just bullet design, it's All Three.