let me explain it (also there's gigantic irony in that statement since most of the time I have no idea what you're talking about most of the time.)
lost levels is cheap because of how it relies on blind jumps (jumping over a giant put only to realize there's a koopa flying up and down off screen and you have to land on it when it's down.), precision platforming (I think 7-3 is a good example here), and most of the time bad designs.
It's one of the many reason I prefer the international version of smb2.
Miyamoto vs Japanese Gamers
Yeah, really, it was more cheap than challenging. There's:
- 4-3 where you have to scroll in the target paratroopa you have to jump on or else you won't make the jump
- All those big green springboard jumps in 7-3 and C-3 where you're off-screen for most of the time and therefore don't have a good idea of where you're going to land (hint: in the pit)
- 3-4 where you have to use a run-through-walls glitch to pass through the route intended for small Mario as big Mario so you can get to Bowser with fire
- 8-3 which most of us Americans first played on the All-Stars version which had no background walls to show us the blocks that were waiting to fake us out right when we jumped over the hammer bros.