Hmmm I used this trig calculator but may have got the angles wrong?
I assumed it was a classic right triangle 30/60/90.
I'm fairly confident that 30-60-90 right triangles have a different aspect ratio than typical displays these days.
I used the Pythagorean c^2 = a^2 + b^2 and no trigonometry.
Assuming square pixels, aspect ratio gives the relationship of a & b -- in this case at 2560x1600 for the M1 MBP we have a 16:10 display, and thus we know that a = 1.6 * b
Thus, c^2 = a^2 + b^2 with a bit of rearranging becomes: b = sqrt ( c^2 / (1 + 1.6^2))
Since we know c = 13.3 then we get b = 7.05 and thus a = 11.28
With a 14.0 display of same aspect ratio, the dimensions become 11.87 x 7.42
That's a 5.25% increase in width and height, giving a 10.8% overall increase screen display area.
Even at 14.4" the increase is around 17% overall area, with 8% width/height increase.
Thus my thought that folks anticipating a substantial apparent display size difference may find themselves disappointed.