NES saved console gaming in USA. No small feat, but different and smaller than the much wider concept of saving gaming worldwide. Much more true would be the claim that Ninty made portable console gaming huge. BTW some people think Ninty invented portable gaming, but this isn't true, Mattel invented single game portables and Milton Bradley invented portables with interchangeable cartridges.
Nowadays we can say that after making portable gaming huge, Ninty saved it merging its user base with Ninty home console users with the Switch hybrid, this was a very intelligent move that kept the user base large enough to compete with the incredibly huge Android and iPhone portable gaming market. This market is an order of magnitude larger, but its gamers spend a lot less on average, with the vast majority just playing free and F2P games, while the vast majority of portable console gamers actually buy at least a few games (and with the welcome not so small minority of Ninty home gamers, we can estimate them to be at least 15M in the worst periods for Ninty, but surely NS success will make them grow again a lot, that typically buys on average more games than portable gamers and FAR more games than very casual typical mobile gamers).