Why is it not as good?
The fighting is not as well done. It is extremely hard to block weapons or thrown weapons unlike River City Ransom which can make fighting difficult.
There are no new moves to unlock via books. This was easily one of the best features of River City Ransom, you only get...
RCR was the most "modern" game on the NES. Not easy to live up to.
Scott Pilgrim wasn't great. I tried the demo on the PS3 and the first few encounters were fun but the game just ground down to nothing pretty quickly. I see the River City Randsom feel for sure though.
In the end, nothing was happening that was of interest to me. OK bad guys, check. Fighting... check. Not a ton beyond that though. Simple is good, this wasn't.