Incorrect. "Loud pipes" are compensation for a small penis.
FWIW, I have several friends that ride bikes. None of them are the sort of people that I would classify as the type that would do something just out of some sort of inferiority complex.
They uniformly tell me that they see loud pipes as a critical safety measure to make drivers aware that they're there.
I do not know if drivers in general (i.e., around the world) are uniformly bad at paying enough attention to notice riders (of bicycles or motorbikes), but certainly here (Brisbane, Australia) people seem to be pretty woeful at their situational awareness when driving.
For me, that is enough to keep me off the road on a bike. I don't even like driving much (my car was new in ~2004 and now has ~38,000km on it).
One of my motorobike riding friends was recently hit by a clueless driver while on a bicycle.
tldr: enough drivers are so bad at being aware of what is aorund them that loud pipes help make riders safer (... or at least, feel safer. I don't know if there is data showing that they are).