I think you're referring to the global zoom level, right?
View attachment 940
You can zoom in smaller increments in a specific panel by holding ctrl while you roll the mouse wheel, but that is temporary.
It wouldn't be a simple matter to make the zoom have more granularity. My suggestion would be to choose a font size that is best at 100%.
Maybe if you can tell me what you need to achieve I can think of a different way?
moving between 2 monitors at times gets crazy