I don't see how that's an issue.
Using photoshop doesn't automatically allow you to post the images. You can post the images IF it was not made/edited by an AI model, regardless of if photoshop was used.
If you use the Stable Diffusion plugin, then you're using stable diffusion, and therefore can't post the image. It doesn't matter at all that you used the photoshop plugin.
LOL how will they even know? Are they going to ask for every .psd and read the entire edit history? what's to stop you making images all day in SD, and when you find one you like, just tracing over it in a new layer?
A lot of Photoshop's built-in tools could arguably qualify as "AI models" (think things like content-aware fill!) - I don't think Getty would say that using them would disqualify your image, but isn't that essentially the same thing, except that this version is ultra high-powered version?
Except they're not. Content aware fill uses only your image as the input and runs space-time video completion. Since it doesn't have to train on datasets, it's not part of the conversation.
Ignoring the philosophical ambiguity, their announcement specifically says this policy change doesn't apply to pictures made with Photoshop.