Less intuitive? Sure, but those who learn it tend to agree it's the better option. Not sure what "dog slow" means, but it's really fast for me, at least when using a fast terminal emulator.

As an example Alacritty+tmux feels wayyy slower than iTerm for tabs/splitting.

Tmux also comes with some limitations that make it annoying (to me) to use 100% of the time :

- scroll back is painful compared to native terminal emulator scrollback, so is mouse support

- rendering gets slowed down by tmux because it parses the output itself, the fastest terminal emulator with tmux will feel slower than iTerm without tmux

- some TUIs work badly in tmux, neovim for instance. I’ve also had issues with htop in the past

Tmux is a great tool, but I can’t conceive using it by default, it’s too janky for that.