It seems like every filtering method available is unable to blend dithering without introducing unwanted artifacts. Every shader I’ve tried falls into one of these two categories.
Gaussian blur - black lines lose all sharpness, destroying a lot of details in pixel art. Highlights get completely blown out. Too much detail is lost.
Lanczos, catmull-rom spline, others - black lines become way too bold, white lines become too thin and the image loses contrast. Ringing artifacts can be a problem.
Do any filtering methods blur dithering without the unwanted side effects?