That's an interesting idea. I should look into that when I eventually upgrade. A stubborn part of me left the monitors in landscape because I occasionally play games, but I end up never doing that on my desktop.
Because I prefer to use the same model of monitor when doing a grid, so I don't think I want to add to my existing setup, because my monitors are discontinued, and they're displayport only for 4K60.
I think they have more than a few years of life left in them, but I'll definitely look into a configuration like yours at upgrade time.