To edit your VSCode settings, use COMMAND + P to open your command palette and search for settings.json. Open the file.
Once open, you can customize VSCode by adding the lines listed below.
The ZoomLevel setting allows you to adjust the size of everything within the VSCode window.
This seems to be the only decent way to adjust the VSCode sidebar size. The approach that I’ve taken is to to adjust this Zoom level so that my sidebar font is at my preferred size, then adjust the other font sizes using the other settings below.
Editor Font Size
Customize font size:
Customize line height: