I'm not imposing my opinion, but in my experience, iterm2 is the slowest terminal emulator I know of, so I didn't even bother trying. But overall, I'll add iterm2 to the list, too.

> far outperforms the likes of kitty and ghostty

this is not true on my machine, at least for my usual benchmark Doom-fire-zig[1]. on said benchmark, ghostty 1.3.1 runs at about 350fps, wezterm 20260713-212414-b3255666 runs at 415fps, Terminal.app runs at 100fps, iterm2 3.6.11 runs at 80fps.

[1]: https://github.com/const-void/DOOM-fire-zig

has iTerm2 improved significantly in the last couple of years? I remember feeling the speedup when I went from iTerm2 to kitty, so that's surprising to me.