I am not sure about resource pack thing but, they could make it optional in Profile -> SettingsI'd not like to see this implented. I think kill sounds are pretty annoying. And yes, the *you know who* server does also have kill sounds.
I think there is some resource pack that you could install instead, you will have to search one up or maybe make one yourself.
I just want it, Its kinda goodWhy you want this?
Is not necesary