No, this is strange indeed.

I wouldn't say that NZ used to be generous in making long haul business class awards available to their *A partners.

But they didn't used to be all that bad, in my experience. Have frequently found the seats I was looking for, especially in June/July.

It really does seem like something has changed given that I don't see business class availability either, at all (though I only checked a broad range of dates for LAX).

Highly unusual.