Because the reality is that most writers in Marvel prefer a white-dominated cast. The minority X-Men like Sunspot, Karma, Jubilee, Dani are all put in Limbo.
The only writer who prefers a multi-ethnic members is Chris Claremont and he introduced a lot like Storm, Karma, Sunspot, Jubilee, Dani, Warpath, Sunfire into the team.
I won't be surprised if you go on denial mode again.
I've been around for decades and didn't hear about Smasher until now.