Complotism leads toward alt right ideaology which means that if you are a complotist you will most likely fall under things such as antisemitism / Antiscientism / Racism / Fascism.
Scientism on the other hand is problematic (less than complotism though) in the fact that it a the belief that science will resolve all the problem. This sometimes lead toward blindness in front of blind spot that science can have like the way that science is still revolving around a patriarcal scheme.