@juse keep in mind that hiding toolbar buttons away behind overflow menus broadly decreases usage of formatting tools. It's not necessarily a bad thing, but something to consider.
Also when tools are dynamically drawn (e.g. on hover over some highlighted text), that breaks accessibility guidelines. a11y isn't why we had a toolbar, although it coincidentally does satisfy accessibility constraints.
I am all for a more streamlined view, and perhaps the default composer isn't there yet, but I also very much dislike UIs that constantly shift elements in and out depending on UI state.
A clean visual field is my preference, and static toolbar buttons, despite taking up space, still work for me.
