It's just the difference between playing the snes as a kid and playing the PS2 as a kid . Age difference will always define what someone deems good
Not to sure about that, I grew up with the PS2 and the SNES currently stands as my favorite 2D system.
Its one thing when you grow up playing the "good" snes games versus learning about them as they were before your time and you then go play them. The nostalgic factor is missing therefore most won't find what some found good about them back then due to various reasons.
I think nostalgia only apples to bad games but people feel nostalgic too, for the most part.
If something is good, it is good, no matter if you experience it new or old. Some things could use a bit of historcal context to enjoy, knowing there limitations of the technology and such, but just because it is old does not mean its bad. If something is actually good, It will stand the test of time and always be good.
Almost all of the things I enjoy are old. Bands like The Beatles, Pink Floyd, Led Zeppelin, Aerosmith, The Rolling Stones, The Doors. I love shows and movies like Police Squad!, Columbo, Animaniacs
(Some episodes are A bit dated, due to "current" references), Tiny Toon Adventures, Loony Tunes, Back To The Future, Monty Python, Faulty Towers, (Minds drawing a blank, I need sleep)
Some things could grow sower with age, I hear people say Golden Eye has aged terribly, I played it once with a friend, I can kinda see why, but Doom holds up well in my eyes.
If by "good" you mean crap games, I understand, but a lot the games listed above are fantastic.
To use another thing as an example, I saw my first complete episode of Star Trek today, The season 1 episode with Khan. I liked it but there were quite a bit of plot problems, like how can a ship of what I can only guess has 100s to 1000s aboard can be taken over by 30 people, why the ship has so many ways to harm the people inside of its rooms (Gas, removal of oxygen) Why Kerk gave Khan the manual to the ship when he just met him, Why the girl, why I think was named Macgiver, was a complete idiot.
I forgot where I was going with this ST thing, But I typed it so its staying here, maybe it will come to me after sleep, its 2 AM.