No. It's true that the market hadn't been molded into what it is today so a lot of them were new and different from everything around them at the time, but that's a testament to their impact on gaming; they helped to set the bar for things to come.
And not everyone who exists today grew up playing games or has had all of the experiences we have. Show someone who is new to gaming (be it a kid or just someone who's never tried it before) a very difficult or complicated game of today compared to a game like Space Invaders, Pac Man, Tetris or Super Mario Bros. Many of Nintendo's classics were some of the great "gateway" games that got people interested, and many of them still play better today than a lot of the current games.
To present anecdotal evidence, in an issue of EGM magazine a few years ago they asked a group of pre-teen kids to play some old classics and give their opinions on them. One kid, who was a huge fan of Wind Waker and other "modern" games, got to try the original NES Zelda for the first time and was drawn in instantly. One of the editors asked, "What would you say if we told you we like this better than Wind Waker?" Despite the simplistic 8-bit graphics and sound, the kid actually agreed.