xterm has a command line flag that enables the same speed hack. It's disabled by default. The major difference between xterm and the others is that xterm emulat

xterm has a command line flag that enables the same speed hack. It's disabled by default. The major difference between xterm and the others is that xterm emulates a terminal and libvte-based emulators, Kitty, and the like are more like shitty xterm emulators. Accuracy is preferred over speed, and certainly over silly microbenchmarks like cat'ing a 655 MiB file to stdout and timing how long it takes to display.