What I cannot figure out is why you're using any form of buttons list. If you want the list of recently trending searches, then get in the search edit box and down arrow, they will be read. If you want some subset of searches you've done before, enter a couple of characters in the search edit box and down arrow.
Your original request states, " I’ve finally noticed a number of what looks like recent shortcuts below the search edit box on the Google homepage." These are not buttons, have never been buttons, and are not accessed as buttons. You just down arrow through them and, in the case of trending searches, these constantly change and may be different if you jump out of the list or edit search box and come right back to it just a moment later.
Brian - Windows 10, 64-Bit, Version 21H1, Build 19043
It is the function of creative men to perceive the relations between thoughts, or things, or forms of expression that may seem utterly different, and to be able to combine them into some new forms--the power to connect the seemingly unconnected.
~ William Plomer