Hide the new lower pane icons?

Is there some way to hide the new lower plan icons?

I never (or practically never) need anythign besides the properties panel, and the way I have my screen setup, it pushes the Set local properties: selector (which I do use) offscreen

No, I’m afraid not, but you should find that you can scroll the tools to the right of the selector buttons, and it should stay put once you have scrolled it to the right.