kitty is much better than the rest on latency, see hardware based measurements https://thume.ca/2020/05/20/making-a-latency-tester/

showing kitty has the same latency as terminal.app on macos.

Those measurements are several years old and thus say essentially nothing about the current generation of these terminals, which are all under very active development.

XTerm is X11 only. Considering that Wayland is much more lightweight than X11, it's hard to imagine XTerm beating e.g. Foot, which is purpose-built for modern Wayland desktops, with almost no abstraction in between.

Not to mention that these terminals have much better overall engineering than XTerm, whose README famously states "This is undoubtedly the most ugly program in the distribution." That line alone is enough for me to avoid XTerm like the plague.

> Considering that Wayland is much more lightweight than X11

That's irrelevant. More relevant is that Wayland is adamant about presenting "perfect frames" (ie no frame tearing), which requires a sync/checkpoint for everything that's displaying, which inherently puts a lower bound on latency that non-sync-respecting X11 isn't subject to.

What's more relevant is that Wayland is adamant on ensuring that scanout is an option as often as possible, making it extremely efficient and fast to put stuff on screen.

Also, every pixel has a "checkpoint" sampled at the display refresh rate. With tearing, the checkpoint of a pixel differs from its neighbors, with each subsequent pixel (leading to rolling shutter artifacts), whereas without, all pixels show the same sample.

At the cost of glitches, tearing and higher render load let's you put slightly newer data in the bottom third or quarter of your screen.

Not really something to write home about, especially considering that X11-users commonly run external compositors exactly to get that tear-free behavior.