Most of the sports included in the Olympics are of western origins. Even games now dominated by China and other Asian countries, like badminton and table tennis, have their origins in the west.
Judo and taekwondo are Japanese and Korean martial arts but very popularly accepted and practised around the world. They're very well organised, structured and standardised, with little or no variance in the practices and rules. Even most Chinese (on mainland or overseas) practises judo or taekwondo instead of wushu.
Wushu doesn't seem to have that reach and appeal. I know that wushu is included in the SEA Games, like the regional game of sepak takraw, but I don't recall theese being included in the Olympics.