Many of the 8-bit games are among my favorites. I gave up on new consoles some years ago - everything felt CGI-ed to death.
My favorite video game of all time is Kaboom! It remains the most enjoyable game in terms of simplicity and hand-eye-coordination.
And I play Adventure on my 2600 almost every day for the past 40 years.
Homebrews for the Atari 2600 and 7800 are still being produced at an incredible clip over on Atariage with a large support base.
It's more than nostalgia for us classic game enthusiasts. Now many games DO suck... but that's true today as well as in 1980. Back then, it took one programmer (who did gameplay, graphics and sound) about 4 months to produce a game. Today it's 1+ years with a team that would rival a movie-studio. And so today game produces don't take chances... they want another Halo or Fallout and probably won't green-light too much original stuff. Back then everything was original - and some of it was amazing and some of it sucked - but the best stuff remains classically playable today.