It depends a lot on genetics. For example landraces only need one male to pollinate the whole field so they have evolved to only have a few males per field. With people breeding the plants, we throw out the males so the plants dont need to evolve away from it.
Ive noticed 10-20% males when growing landraces and oldschool stuff but a lot of the modern day genetics have been more around 40-60% males. I cant tell you how many packs of ocean grown seeds ive grown and have only had like 3 or 4 females out of them all. Was more like 60-80% male.