I know what you mean and that's partially why Call of Duty 4 is actually my least favorite out of the modern ones. It's too easy to run around like a chicken with your head cut off, spraying headshots from the hip, proning, reloading, and doing it all over again. That gets you killed in the later games. You have to play smarter and that makes it much more rewarding when you get the super high customizable and controllable killstreaks. The first time I earned an AC-130 was a very special moment for me

But back on point, I think it's a very weak argument to say it doesn't matter that KB&M is more inconvenient than controller, because these are things that you personally don't use. I'm wondering if the reason why you don't use these things is because it's impractical for you to use equipment and tactical grenades in the heat of a firefight quickly and effectively, due to how it's mapped for PC. A cool tactic is to pull out C4, throw it through a window and remotely detonate it. It's incredibly effective because C4 has such a larger blast radius than a grenade. I could never imagine myself doing that on PC.