> tmux was always a better option for that kind of functionality anyway

Not sure a lot of people would agree. Tmux is way less intuitive than tabs/split panes directly supported by the terminal emulator. Also tmux is dog slow compared to native tabs.

iTerm split panes use such intuitive keybinds I find myself changing other software with similar functionality to match, e.g.

split pane vertical: cmd + D

split pane horizontal: cmd + shift + D

focus pane left: cmd + [

focus pane right: cmd + ]

Just gold standard imo. tmux is great software and very useful on remote machines but its keybinds don't come close.