@AshDene I haven't encountered that in an RTS. I have in 4X, though. I don't think being that far zoomed out on an RTS would be helpful - you'd lose track of units, micro would become incredibly difficult if not impossible, and the FoW would become a lot weaker. It doesn't seem to fit the genre design, in my opinion.
Not to mention the accessibility nightmare it would be for the visually impaired.
Basically all the Total Annihilation clones allow you to zoom out to see the entire map and are designed to be controllable like that (units turn into small icons and such).
You can try this gratis and open-source one: https://www.beyondallreason.info/
Waronoi - while not exactly what you are looking for - plays with zoom- and detail levels. It’s good and fun.
In Total Commander / Bejond All Reason apparently good players spend most of the match in a very zoomed out tactical map.
In general I think the Total Commander genre is one of the few that allows a somewhat usable total view. Another good candidate would be Homeworld, since there microng is not that important so you can probably play a whole game on the starmap.
Other cheating answer would include... Very small old rts on modern screens. I think a smallsized AoE II map on original resolution would fit on 4k panel...