I can feel ya on that. Bowie almost had monotonic approach to singing verses. He wasn't a particularly skilled singer, but he knew how to manipulate his voice and use it to stay interesting and keep the listener guessing.

Prince's vocal kind of falls into that monotonic area a bit. It's sang in a lower register to begin with, and it was probably approached as a guide vocal. I would imagine if he had intended to release it, he may have rerecorded that vocal a bit.

But the version as it stands definitely has that monotone Bowie vibe.

Prince's "Yo Mister" is the only Prince version of a song that I like less than the one recorded by anyone else. I guess the monotone voice is what does it?
It's not really a guide vocal. It's more just fitting the words into the production.

there are many words i would use to describe this vocal on this recording, but monotone is not one of them...

Y'all really get stuck on one word and run with it, huh? Okay then.

I get a Camille and Patti LaBelle vibe.

The Patti thing is probably just psychological because she sang it but just read on Pvault the basic tracks were recorded in Nov 86 just 6 days after the Camille album..