hmm it seems as suspected this is a CSOUND problem , judging from this
https://forum-next.cabbageaudio.com/t/cpu-overload-how-to-optimize-this-code/1109
if this dude has an issue with just a typical supersaw its no wonder I have such problems myself with even more voices (32 is basically the minimum for me after that I get audio dropouts) and he is dead wrong , 32 voices is nothing even for my 10 year old Yamaha Motif ES6 which can easily output 128 , it seems he experiences the exact same issue as I have.
Nonetheless I will keep investigating but from the looks of it CSOUND C API is my only ideal option right now.