I don’t know how often I heard the claim that ALL calicos are female. This is not the case. While most calico cats are female, there is the occasional male. Fact is that the majority of those calico males are sterile, because the color is linked to the sex.
Calicos require two X chromosomes which means the cat is a female. On some rare occasions however, a male calico will be born. The cause is usually an extra chromosome; instead of him having XY, he has XXY. About 1 - 3000 calico cats turn out to be a male and out of those males only 1-10,000 are fertile.
I also heard the myth that all orange cats are male
That can’t be true, because right at this moment I am looking at 2 orange kittens that I have raised a male and a female; brother and sister. The reason is that the orange male needs one copy of the O gene to produce an orange coat where the female requires the O to be on both chromosomes. If she has only one O she would turn out a Calico.