Yeah, and it pissed me off that men are depicted as bumbling idiots on TV as well. Everyone judges everyone else by appearance, perceived class, whatever. We as humans make millions of assumptions based on our prior experience. It is natural.
In reality, there are differences in people, things, everything. Sometimes we can those differences just by seeing them.
Modern society seems bent on making everything equal. The brains and bodies of different gendered people are different. Some people are smarter than others, some people are stronger than others. You can't make them equal. I am tall. You can't hold me to the same rules as a short person. I cannot do gymnastics for example.
Now, with gender in IT. There are few female IT people. I like just about everyone on steemit works in IT. I have worked at various companies. Male IT workers outnumber female IT workers 100 to 1. Easy.
So, maybe lighten up on someone who assumes you are not the IT guy. I bet I worked at a nail salon and I sat down to do someone's nails their response would be very similar to what you experience.