[Klashikari]

I didn't even think about sexism, since it isn't like Asuna can't do anything (I personally am not in that group of people thinking that Asuna is a mere damsell in distress in ALO, so no mysoginist setup perspective for me).

What actually doesn't work here is how the author had to slap a fetish in such manner with absolutely no regards of actual logic with his own setup, similarly how he had to pull a "non blood related sister that falls in love with the protagonist", but in a far more dubious and crude manner. That's about it.
That's a bit similar how we have school swimsuits being introduced in a adult environnement like Muv Luv: it is nonsensical and evidently otaku pandering feature that adds nothing to the story.