I tried the approach stated on https://www.telerik.com/forums/change-row-height-in-week-and-day-view, but this only allows a minimum row height of around 22 pixels.
I found some old code of mine, which allowed the desired height (about 16 pixels), but the code only works up to version 2021.3
See https://dojo.telerik.com/AvOkisad which uses ".k-scheduler-table td,.k-scheduler-table th { height: 1em }"
How can this be achieved in the latest release, as you can see it doesn't work as shown here https://dojo.telerik.com/iYoCobuG