There are certainly tools out there using Stable DIffusion and the like to use neural networks to generate normal maps from photos. The problem is they mostly rely on illegally-scraped datasets. If you're OK with the ethical and legal issues of that (I'm very much not cool with it) then have at it.…
Niche example: old-ish game moves to new engine or you are making enhanced edition. Doesn't happen that often, but when it does, you are sitting there with hundreds of diffuse textures that need normal maps now. Possibly also roughness, metallic etc. Recreating them properly in designer would take too much time/money.…