Chlöe Swarbrick spoke in the NZ Parliament and said something ageist: "OK boomer", which expresses bigotry against old people.

What she says in the article seems valid to me. Also, if I lived in her district I would probably vote for her, since she is in the Green Party. Nonetheless, using the ageist rebuke is not right, and I hope she will avoid it in the future. If an old white man does something unfair to her, he deserves criticism for his conduct (and perhaps his political stand), not for his age.