I'm in the midst of playing Deus Ex for the first time right now and I can say without a doubt that it's the greatest game of all time and that older games are largely better. Games were great when it was a large smattering of small, creative studios trying to do fun, interesting things with a new medium. As said new medium gained in popularity, and therefore monetary viability, corporate interests became involved and now the vast majority of games are put out by large super-publishers as a means to an end (getting your money quickly).
Sony and Microsoft ARE NOT full time games publishers, they are enormous media corporations that publish games, and so the games they put out are only as valuable as the money their shareholders predict they're going to make. So most games for PS3 and Xbox 360, which just so happen to be the consoles with the best technology, will be bland, generic, derivative, and predictable, until consumer interests radically change and ten or so years are provided for the suits to notice said change.
Nintendo actually used to be one of the fun creative studios and many of the people working there, particularly Miyamoto, retain that spirit, but they are deathly afraid of change, despite what the Wii, DS, and 3DS might suggest. The creative direction at Nintendo is overseen the same cabal of eight or so Japanese guys it was in the eighties, and that's not going to change. Right now, if Miyamoto were to suddenly die today, there would be no Nintendo tomorrow. Their entire economic model is rehashing franchises he invented plus Pokemon. Every time we say old games are better, we reinforce their fear of true innovation. New technology is one thing, but new franchises, new forms of gameplay, new genres? Absolutely not. So while old games may indeed be better, the people who made them need to grow up if we're ever going to get more classics. I don't think we'll ever stop seeing Mario or Link, and I don't think we ever truly would want to, but Nintendo could be so much more than just the company that makes Miyamoto's games.
Activision and EA are the epitome of evil corporate games machines, and as long as you keep buying the shit they put out, they'll keep putting out more shit. Oh, and buying out good studios and stealing their souls.
However, PC publishers like Valve and the scattered disciples of Warren Spector, as well as the entirety of the Indie Games scene are all making great games right now and have the right idea, and if video games can work past their weird corporate adolescence, the "by gamers for gamers" future is on the horizon with these kind of people in charge.
tl;dr video games were fun until YOU started paying for them