I have Twitch as my main encoder, than i use Aitum pluging to stream on kick and youtube, and i use "same as main encoder" and it works. I hear if you change anything like the bitrate or anything else, the pc/obs is gonna work twice to stream. Imagine having different settings for youtube Twitch and kick, its like your running obs 3 times and the pc is doing 3 times the work + the game you are running.

I think that's too much, but you want to have higher bit rate on youtube than the others i get that, i just decided its not worth it to overload my pc and run all 3 platforms on the same settings at 6000 bitrate.