Unions aren't mentioned at all in the article. Your claim is also a bald faced lie. More so than the OP. This article supports OP's claim https://nypost.com/2023/03/16/nys-education-leaders-again-pr..., I can trivially find other articles from other sources where the New York teachers union has made it clear they dont find how they are evaluated by test scores acceptable. That may even be a reasonable position to have. There is more data out their to support OPs claim than yours that they are against it.
If one actually reads it, it's just a recapitulation of TFA. "SED", the organization the editorial rails against, isn't a teacher's union, you know -- it's the State Education Department. ctrl+f for "union" in that piece, and beyond a reference to the Times Union article, the only involvement of a teachers' union is at the end, where the editorial's author claims that the union is the only beneficiary of these shenanigans, and implies that they had a dastardly hand in anointing the Assembly Speaker.
If there were other articles from other sources that you could trivially find, why didn't you use them? Why use this and misrepresent what it said?
The link provided shows that, in fact, the union opposed the change. This claim is a bald faced lie, and lies should be downvoted on HN.