Most of these emulators go in the S-tier for me. The only one that I find a little laggy is iTerm2, but it's still a featureful terminal with great MacOS support. Also, admittedly, I haven't used Warp terminal extensively. That one has a lot of promise with its modern AI features, though. Take my ratings with a grain of salt— I'm definitely prioritizing performance above other factors.
Alacritty

Joe Wilm (individual)
https://alacritty.org/
This was my main terminal for a long time. I stopped and switched to WezTerm for undercurl and ligature support. It's heckin' fast.
- Zippy AF
- No official ligature support
- Rust
Ghostty

Mitchell Hashimoto (individual)
https://ghostty.org/
This is the newest of the bunch. It was created by Mitchell Hashimoto (the person behind Vagrant and HashiCorp) and has been hyped up— for good reason.
- Zippy AF
- Zig
- Ligatures
- Undercurl
- Image support (with
+kitty
image protocol) - Built-in splits and tabs
iTerm2

Free Software Foundation, Inc. (company)
https://iterm2.com/
This emulator has a lot of configuration options with native MacOS support. It can feel a little laggy once you start using the faster terminals.
- Fast, but not Alacritty or Ghostty fast
- Integrates seamlessly with MacOS
- Built-in splits and tabs
Kitty

Kovid Goyal (individual)
https://sw.kovidgoyal.net/kitty/
I used Kitty for a short time, but I might have to revisit it later. It is zippy— but perhaps still not as zippy as Ghostty or Alacritty. Another cool feature is image support and multiple font sizes!
- Fast
- Built-in Neovide -like cursor animations
- Built-in image support
- Built-in splits
Warp

Warp (company)
https://www.warp.dev/
I haven't used Warp extensively, but the concept is really exciting— built-in AI helpers for coding.
- Rust
- Built-in splits
- Integrated AI tools like LLM chat
WezTerm

Wez Furlong (individual)
https://wezfurlong.org/wezterm/index.html
WezTerm was my daily driver for a long time. As a Neovim user, I love the Lua configuration. I would be using it still if Ghostty wasn't so damn fast.
- Fast, but still not Alacritty or Ghostty fast
- Rust (configured in Lua)
- Built-in splits and tabs
- Ligatures
- Undercurl