What used to be a more or less solid black line, turned into a grainy line.
I allways like the tech pencil for being a sharp, crisp line, almost like 3D document would get you, but with the option of giving it a bit of the overstretch to make it, well, sketchy.
Great for overlaying on your colour renders subtly to give edges more definition and make the whole thing look a bit more like illustration. This effect is pretty much ruined by the whole grainy linework you get out of ArchiCAD20 at the moment.
I've reported it as a bug to the dutch reseller.
Unrelated, I also notice that the 3D views don't match up between 19 and 20. The horizon seems to have dropped a bit, for lack of better explanation. Excact same camera settings make the bottom end of my model disappear in 20. I've reported this too.
This is a recently reported issue. A coding change had a negative effect on the Paper Roughness setting. As Marc noticed above, set the Paper Roughness to 0% in the PhotoRendering Settings palette and the quality should be as you might expect it.
Sorry for the inconvenience. This is planned to be fixed in a future Update for ARCHICAD 20.