The list of functions that can be added to the QAT when clicking the "new" "Customize Quick Access Toolbar" is new, and I found confusing at first. That is the button I want to remove.
Any item you find in the existing Ribbons and most drop-downs in the ribbons can be right-clicked and added to the QAT.
The Select All command is On the Home Ribbon, Editing section, "Select" drop-down list, Select All.
Another option, a little extreme, is to Customize the Ribbon with a custom Ribbon and add the tools you use there and make that Custom ribbon the first Ribbon item, before Home in the list.