iTerm2 actually offers nice interfacing with tmux. If you run `tmux -CC` it will start a tmux session that iTerm abstracts away letting you split and switch panes as you normally would in iTerm, but still allowing you to join the tmux session on another terminal.
For some reason I kept getting extreme slowdowns/laggy behaviour when using neovim.
I’ve seen this thread: https://github.com/tmux/tmux/issues/353
I tried everything in the thread and still end up with a laggy terminal. For now I just use iterm2 with tabs but I miss my tmux.
On my personal Linux laptop, I never encounter the same lag with the same setup.