I swear, this reign of visual artists as dictators has to stop. I'm sure people noticed this issue internally and brought it up but some thing by some designer was seen as biblically sacred and overruled all reason. I've been at companies were you get severely punished... sometimes fired for subordination for fixing an obviously broken spec by a designer emperor. It's normal to be "I guess 2+2=5 here, whatever" as if…
Seems like you could make the corners round (not making a judgement on that in any way) and still give the resize handle a more sensible size/shape/location right? As in this isn't a visual design problem.
When Windows went to a 1 pixel border and shadow effects, it still had hit testing in a region around the window to account for that. No idea what they're doing with rounded corners in Win11.