The Pro Display XDR always had mini-LED. It has 384 FALD zones, if I recall correctly.
384 LEDs doesn't necessarily make the LEDs 'mini' in size. For a 6" screen. Very probably yes they are abnormally small , because there is not that much area to distribute hundreds of LEDs into. For a 32" display.... no.
Mini (and Micro) LEDs have to with size of the LEDs; not the number of zones.
" ... Mini LEDs are smaller than the average LED, with diodes that measure in the 0.008-inch (200 microns) range, or about a fifth the size of what a standard LED measures. ...
...
Not to be confused with mini-LED, micro-LEDs are even tinier, and offer a much bigger change to TV technology. Current micro-LED sizes are as small as 50μm — about 0.002 inches across — making them 1/100th the size of a conventional LED. ..."
Smaller and smaller LEDs mean big improvements for TV displays
www.tomsguide.com
A standard/conventional LED is not that big relative to a 32" display.
For 384 zones then can have a rectangle of 32 x 12 grid. For a 6016 x 3384 screen( @ 218 pixels/inch). That is 188 x 282 pixel rectangle ( pretty close to being a 1" x 1" square ) . That really isn't smaller than a standard/conventional LED ( in the 0.1 inch range. ) .
For 576 things wouldn't work out much 'worse' for regular LEDs either. (32 x 18 grid) Still not going to be in the small fraction of an inch zone ( 188 x 118 a bit under a inch but not by wide margin.).
The MacBook Pros have had mini-LED displays with many more zones (thousands), and it shows.
Yes. For a substantially smaller size screen the LEDs in the thousands need be smaller.
They are awesome displays, until OLED becomes viable (cost/burn-in). I keep wondering where the real, cheaper, mini-LED Apple monitors are.
More a matter of margins for Apple. One doing recoup on investments made into the current XDR. And waiting for production costs to go lower panel cost for next gen XDR.
A decade from now we might get micro-LED, and perhaps reach endgame, until headsets just laser the display onto our retinas.
Somewhat dubious that lsser onto retina is a healthy alternative for extended long term exposure.