I actually made some progress in this matter and can report as follows:
• when I upgraded the print driver, somehow the printer got switched to the AirPrint driver and not the native Xerox driver in the Apple 'Print' settings. When I deleted the printer and re-added it, it still selected the AirPrint driver, and I had to manually select the Xerox driver
• once I had the native Xerox driver selected, then in Adobe Reader, the advanced settings page was then enabled and for some reason the 'print as image' option was selected. When I de-selected that option, the problem was fixed and .pdf's print normally from it again
I see no one has responded to this post yet. So, at this point I would recommend contacting your local Xerox Support Department to speak with a Product Specialist for more assistance. Please call 1-800-821-2797.
OS: MacOS Sonoma. On Jan 22, 2024, I installed the latest Xerox driver for MacOS and installed the WorkCentre's latest firmware. After the updates, .pdf's printed from Adobe Acrobat now print very lightly, with the black text now a light gray. Most .pdf's printed from Apple Preview print just fine still, although a few also print lightly. I have tried changing various settings, and I have tried forcing the printer to print just under black & white mode, but nothing helps.