Compliment women (not only girls) "by default" on their looks actually drives me nuts. It's used even in situations where is totally irrelevant (e.g. radio show). It is really engraved n our culture.
I agree with you, that visual observable complements, over sound-only channels are pointless and frustrating to hear.
But, does it hurt you, that women want to look pretty? Would you like your daughter to be indistinguishable from a boy?
I certainly would feel this world being a crappy place if women were as awful with their appearence men.
My comment was controversial opinion, to the "girls shall not be encouraged to look pretty".
Likewise, sadly concentrating on being pretty is a viable strategy for women. It's not that they can't do anything else, but they have this option (much more so than men).
Although apparently good looking men have advantages, including on average higher salary. So it doesn't hurt, but it's only a supplement.