Looks are considered far more important for a girl than for a boy.”
Ask most girls who are dating and if they are honest,they will tell you differently. They want a boy who is attractive to them also, and if he is overweight, slovenly, unkempt or has bad breath, they WILL notice. Everyone wants to be attracted to their zivug.
As to the “Y” chromosome being one thing or another, or guys ideally looking for thin girls, it seems Hashem Himself made the decision that girls OUGHT to be heavier, as He created girls to be a 2X. :::fleeing now::: (I am not explaining this to guys who may not get this reference).