I definitely agree that I want to type some string and it should show a fuzzy search from all available commands and their descriptions. That would be huge timesaver for functionality I know exist, but I forgot the exact commands.
If I'm not mistaken when you install vanilla Emacs the screen even includes a tutorial and guided tour that both tell you these commands.
Example : I want to change the encoding of a file when I load it... Good luck figuring that out without resorting to reading the documentation.
Again when you load emacs there's a link to the manual on its splash screen and as a guided tour. A lot of people rush to turn off this screen or suppress the menues on startup (which I get, the menu bar is pretty ugly) but they do have useful functionality for someone who doesn't know Emacs.