AFAIK the reason that it hasn’t been supported so far is because of the additional fees and or hardware necessary for hdcp protection of the signal. Either way Google will be eating this new cost or raising the prices to compensate.

Got it on my Pixel 6 Pro, cinematic wallpaper hangs when I try to use a photo from a shared Google photo album.

Edit: Worked the second time I tried. Impressed by the cutout, seems better than the fake bokeh blur cutouts.