Well OP, many Xenoblade Chronicles (Wii) fans are in denial and blinded by nostalgia and the Wii's poor graphics. They don't want to accept the series history.
But want to hear my theory? Bright colors = bad, immature, childish and anime. Look at how many people complained that Definitive Edition was "anime" now when the upgraded graphics were revealed.
Xenoblade Chronicles 2 has a more shiny, saturated/bold color palette and more cartoony/exaggerated proportions on characters. So it naturally draws your attention more.
While Xenoblade Chronicles on the Wii had slightly more realistic character proportions and a very muted color palette. It was also on the Wii and very blurry.
It's the same reason Xenosaga never gets brought up as much, because Episode III was also more de-saturated in it's color palette and had more realistic shading for characters.
Pyra isn't introduced by her boobs, you see her whole body first.
BUTt, Lorithia is introduced by her butt crack.