Actually, Nintendo showing up right after the crash is what made things tougher for them. They were able to get into stores, which were very understandably worried about all the worthless gaming stuff they still had, only by offering to buy back any unsold product. Adding to this, the "seal of quality" was what was needed to convince stores to give the shelf space back to games.
As for where we would be if Nintendo hadn't done that, I really don't know. To my knowledge, Atari did not offer those assurances with the 7800, so it wouldn't have gotten anywhere. I don't know if Sega offered it for the Master System; if they did, they may very well have been in Nintendo's shoes today.
-dunno001
-On a quest for the truly perfect game; I don't think it exists...
