> among the myriad hashtags that accompanied each image, not one mentioned A.I. art or generative art.

He's pretty haphazard with his hashtagging - changing the style and contents over time - but his very first post has the #ai #aiart hashtags (as well as #naturephotography) and it seems to pop up every now and then

https://www.instagram.com/p/CjqQF9zuvkW/

If I were a real photographer I might get upset that my photos were being used by the tool he used. But there's so much use of filters and staged lifestyle photos on Instagram I'm not sure he really deserves the hate he's getting