Why are these products gender-stereotyped?

do women really want pink with flowery smells and men really want blue with strong scents?
are there biological differences to our nutritional needs?
does having one product for women and one for men mean that a company sells twice as many items?
why are the ‘female’ versions of products often more expensive, and in a different part of the shop?
I can see that maybe shaving needs are different, and that hair loss products may need to be specially formulated for men’s and women’s different hair growth needs, but what about things like pens? Surely the ‘pens for girls’ and ‘toothpaste for men’ products are not necessary?
would a man be embarrassed to use a product that was designed for a woman? What happens if he has long curly hair with special needs?
why can’t everyone’s products all be in the same place and non-generdered so we can choose what we like? This applies particularly to children’s clothes and toys!

Personally I wear men’s