I actually migrated away from tmux because I became tired of using one set of keybindings to manage my terminal windows... and another set for every other os window. I also wanted gui apps being part of the session, not just terminals.
So claude and I grew the replacement over the course of a few months. Really happy with it. Never looked back.
Oh yeah. I actually use Forge[0] on my Linux desktop machine at home which allows me to customize the keyboard shortcuts for tiling and managing OS windows.
Unfortunately I still have to use macOS and Windows at work, so universal OS window management isn’t a solved problem. I’m happy enough that I can run Emacs everywhere and have consistent keybindings inside Emacs though.
[0]: https://extensions.gnome.org/extension/4481/forge/