Yes, it matters, not least because the legalities and ethics surrounding these AIs are nowhere near resolved. WotC won't go near it, and I wouldn't want them to for the sake of professional artists.
I think pure AI art is going to be the province of small time players, but I think some AI art will find its way into most rpg releases in the not too distant future. I think it may ultimately end up being less a matter of expense and more a matter of needing things generated last minute to fit particular specifications.
I think this is right. This sort of "AI" tool will be detrimental to freelance artists, but a boon for writers/creators with limited budget, time, and/or artistic ability. One group benefits at the expense of another. In that sense, it's just another chapter in the book of automation.
That said, there are certainly huge ethical question marks hanging over the issue. Using generic or "self-orchestrated" AI art is one thing, but using AI art to mimic the style of a specific artist is something else entirely, like if someone created a Planescape-y setting using AI art that looks deTerlizzi-esque. That would be a definite no-go for me.
I can see these tools going in so many directions with respect to monetization models; royalties; protections for artists and corporate IP; variant training data sets (eg, cheaper ones trained only on public domain, pricier ones include copyrighted imagery?); user interfaces; consent for models; and so forth.
It's certainly an intriguing development, with ramifications that go far
beyond D&D books.