I think there is still some use to diction. For me it’s a great way to get screenplays on paper. I can type fast but I can think and speak faster. I just record a stream of thought of the story/video I want, even if I jump all over the place it doesn’t matter, just a nice stream of consciousness. Afterwards I spend time editing and putting things in the right order and clean up. I find this much faster than just writing.
I use whisperfile which is a multiplatform implementation of whisper that works really well.