@Hunterrules0_o @hanser @nblr X11 was developed and Xorg carries a legacy from a time where computers where resource constraint and you had to be mindful about how you'd spend CPU cycles and memory.
Wayland is the result of a mindset that developed in a time where screen resolutions were still small (XGA, and memory "plenty"; ~1GiB), and you could easily fit 512 screen-fulls of pixels into VRAM.
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@Hunterrules0_o @hanser @nblr
These days we have 4k HDR screens. Such a screen's framebuffer comes in at 2×32MiB (double buffering). And in a compositor based graphics system such as Wayland, each every window will hog up to 32 MiB, even if minimized or otherwise hidden, so that quick preview will work.
For 8k screens you've multiply those numbers ×4. Assuming a GPU with 8GiB VRAM that's just 250 windows you can fit in there.
And of course you've to bear the needed memory bandwidth, too.
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