To the point where I question the legitimacy of including stock coolers with such demanding processors.

My own Wraith Prism is just sitting in the basement, and I don't see myself ever using it, unless something happens to my high-end cooling system and I need to install something while getting it fixed, at which point it'll go back to the basement again.

It would be interesting to see statistics on how many Wraith Prism coolers sold together with 3900X CPU:s actually end up being used. I expect the number to be quite low.