Ehhhhhh hard ass real time stuff like heavy dsp or a game engine, you're on the metal and you're pitching your code to the CPU, not to humans. And the CPU thinks (kind of) imperatively. And the GPU does its own thing which is basically neither, haha.

Stuff like web apps, or honestly, the vast, vast majority of programming, functional is just fine. The deep stuff is gonna stay imperative, but that's a small fraction of the work that needs doing out there.