Almost definitely not hate speech. I know we're all out for blood, but be reasonable people. I see people say "If he said that about any other race he'd be ceremonially shot in the street", and though It may be true that he might get more shit for it... People do say stuff like that about other races and are fine, at least legally. He said white people can't cook for god's sake, not that they should be executed. It's racist but not hate speech, not even in the socialist republic of Canada, definitely not in New York (where Uki lives as far as I know).
Also I find it incredibly funny that the guy who posted Uki's tweet on the Niji reddit has
himself been racist towards Chinese people, although much more overt. Which is crazy when he's coming to the support of a Chinese woman.