Yes, a pinhole zoom lens does exist thanks to the Chinese company Thingyfy. Ephotozine reports that at the 2019 Photography Show Thingyfy were showing their new range of pinhole lenses which includes also the world's first pinhole zoom lens, the Pinhole Pro X (not sure that "Pro" stands for here).
Thingyfy pinhole lenses are sold at Amazon.
Additional pictures of the new Thingyfy Pro X pinhole zoom lens:
