I'd say up to a couple of hundred is much more than 40. Not a full decimal order of magnitude, but even without compression the 170KB on one side is up to 4½×.
However, very few tapeloader games ever tried to load more assets from tape. Generally it would just load a memory image and that would be that for the entire game.
You can access nearly 64kb of RAM on the C64, if you don't need the BASIC or Kernal (sic) ROMs. They can be software toggled in or out. Agreed that even the tape had more game data than that, but not much more.
But that's also kind of what makes it impressive in a different way. Even if the game was larger on disk/tape, they still had to stream it in tiny chunks and make it run within those constraints