The side ribbon of VSCode is called the Activity Bar. You can put it on top of the sidebar (making it more like a tab bar) or disable it entirely (which makes it a lot harder to open the sidebar or change the page it's on).

It's as simple as right click it -> Activity Bar Position -> ...

Can't you use the command palette to switch views? With enough muscle memory, this is always faster than the mouse, in my experience.

You can just disable it in the settings, quite a lot easier than building a new version without it.