Why do feminist consider it offensive for a woman to make a man a plate?

Why do feminist consider it offensive for a woman to make a man a plate?
My ex and I were at a family gathering and I asked her to make me a plate and she said no so I asked my little sister and she asked me what I wanted and brought me a plate my ex got mad at my sister for bringing me food “That’s sexist and demeaning” like I demanded that she do it she was happy to oblige I don’t see anything wrong with it but if you’re a woman and you find that sexist please explain to me how?
Why do feminist consider it offensive for a woman to make a man a plate?
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