Alacritty has fewer features (by design) i think. Alacritty is more supposed to be used with something like screen or tmux while Kitty has tabs, splits and so on.
My understanding with Alacritty is that functionality like tabs would be up to downstream software to implement. So I create a new project called "UltraAwesomeTerminal" and use Alacritty as a library.
Is that accurate? I'm kind of unsure.
Our position is that tabs is the job for your window manager. I, for example, run `i3` which makes implementing tabs in Alacritty a non-issue for me.