I don't have 'Use mouse wheel to zoom' selected, so it shouldn't zoom, but I do have 'Use scrubby' zoom' selected, but I don't know what scrubby zoom is. I shall de-select scrubby zoom and see if this fixes the problem.
I don't know if this is a bug or a 'feature'. When I turn the mouse wheel I move forward and backward through the pages in the publication. If I move the mouse wheel fast the pages seem to zoom out so that I have many pages displayed on the screen at the same time. Below I had the page at full screen width. I turned the mouse wheel rapidly to move through the pages, and now have many small pages displayed. My system is Windows 10 Affinity is 184.108.40.2061