No offense but this “Linux is the kernel” discussion is what I really hate about the whole Linux community. If a software like Renoise “claims” to run on Linux it means that you have to have the regular “desktop”-linuxes like Mint, Ubuntu or (in my case) EndeavourOS
I never had issues installing renoise with the ./install.sh - script. Not even on my Raspi or my Steam Deck.
Concerning realtime/cpupower stuff: I wrote a complete tutorial here Arch-Linux: Best settings for realtime and low latency