Yeah weird shit does happen in nature, but it evolved to happen over millions of years. Conversely, cannabis evolved to be dioecious and have distinct sex chromosomes over millions of years, which means there’s no recombination between the sex chromosomes at all. Many dioecious plants only have proto-sex chromosomes, meaning the differing X and Y chromosomes still have some recombination. Not cannabis, which indicates that the sex determination evolved long, long ago.
The argument that true males from fem pollen, meaning males that will produce both male and female offspring, is arguing that a spontaneous mutation arose that led to an entirely new sex determination factor. While theoretically possible, it’s on the one in a billion type of possibility. Way, way less than the “1:3000” or whatever odds people like to throw out.
The way, WAY more likely reason for males is either pollen contamination (unless you’ve never had males grown in the same area there’s no way you can guarantee that it hasn’t happened) or they are extreme herms that are still genetically female and their pollen will only produce female offspring.
I’m not saying people won’t see male appearing plants in fem crosses. That I believe. I’m saying if it was truly pollinated by fem pollen, it’s not a true male.