Comment by deaddodo

Explorer.exe is not file explorer, it is the Windows UI system. It’s harder to see on modern Windows versions (since Windows will reload it automatically), but if you go into Win98 and kill the process, you’ll see your taskbar, desktop icons, right click menu, etc disappear.

File explorer is a part of that process, but consists of additional dynamic libraries and COM components that are loaded on-demand.

Old desktop replacements (like Litestep) specifically modified Windows to block explorer from loading the desktop to replace it (though, would still spawn it for file explorer).