> Can the compositor replicate the input-to-pixel latency of uncomposited x11 on low-end devices or is that a class of performance we just have to sacrifice for the frame-perfect rendering of wayland?
well, the answer is just no, wayland has been consistently slower than X11 and nothing running on top can't really go around that
> wayland has been consistently slower than X11
Wayland is a specification, it has an inability to be "faster" than other options. That's like saying JSON is 5% slower than Word.
And as for the implementations being slower than X, that also doesn't reflect reality.
There is no Wayland to run on top of as its a standard to implement rather than a server to talk to.
Can you cite any sources for that claim? I found this blog post that says wayland is pretty much on par with X11 except for XWayland, which should be considered a band-aid only anyways: https://davidjusto.com/articles/m2p-latency/