Yeah, another gotcha is that my MBA can't even drive a single 4k display at 60FPS, which I'm not sure was visible anywhere on the product page. (Not sure whether this limitation holds for the M1 MBA).
Yep, that was particularly disappointing to me. My 1440p panel supports up to 144hz, but MacOS only acknowledged 50hz and 60hz for the panel. Not that it made much of a difference in the first place, a flashing panel at 60hz is just as unusable as a flashing panel at 144hz.