ranger and its clones. sane defaults (tho i would prefer if the borders were on by default, at least when not in a tty), extensions, customizations and a very fast builtin hotkey popup (when pressing y for yank it the lists all related options and hotkeys)
but in the end it is a very simple but powerful file manager that works locally and over ssh, to the point that i dont even have a graphical one installed anymore
the greatest strength of obsidian is the plugin eco-system. doesnt matter how good the alternative is to vanilla obsidian, it has to compete with the ecosystem