see link above. for a bit of my process ive been primarily printing form my “11x17 Plan” layout tab using the Rhino Pdf driver set for vector output but to no avail (note this has happened from every tab, every time, this just happens to be my most common printing process
I just had this problem and figured it out. I know you posted this a long ago but I’ll just put this here for anyone else.
Double click into the viewport box on your layout page and set the display mode to Wireframe. It seems like any other mode makes the print result rasterized. I was in ghosted when I had this issue.