Well, first of all, I don't buy the idea that there is a clear line between 'filter' and 'generative' AI. Even in the example Krita dev posted [0], you can see the 'filter' AI made up a bit detail (the way the girl's eyes look became different), it's just not as smart as so-called generative AI.
And about the privacy and copyright concern, what we currently have are:
Stable Diffusion: local and offline, but not copyright-clean.
Adobe Firefly: online, but copyright-clean (if we believe Adobe's claim).
So if we combine the better sides of both, it suddenly becomes okay?
[0]: https://krita-artists.org/uploads/default/original/3X/1/4/14...