I think the key distinction is the consistent layout (main pane + stack) along with keyboard shortcuts to manage. To me it's similar to running vanilla X{11,org} vs using a window manager (hence the name). A vanilla configuration will work just fine but sometimes a constrained or opinionated environment gets more out of your way and better fits your preferred workflow.

If you already have a robust tmux workflow with a desired layout (or lack of layout) and custom keyboard shortcuts then this may not work for you. It's just one way to manage panes/windows in tmux that I hadn't seen before and different from the usual ad hoc methods.

Like most window managers, I think it's all preference. What're your current preferences for pane layout, window management, etc? Do you always create/layout panes in the same way or is it situationally dependent?