Ruined is definitely not the right word for what has happened to the Pokemon franchise. Much like the Pokemon themselves, the series has evolved. There will always be people that prefer the original, unevolved versions of a Pokemon (say Bulbasaur), but as a Pokemon evolves (into Ivysaur then Venusaur), there's no denying that it's more powerful than it was before, even though some will stand by their unevolved partners. This holds true for the games, too. As technology progresses, the visuals, mechanics and details of the game move forward. Some may see these changes as "fast, confusing and boring", but I'd say the majority are excited about the changes, and can't wait to see what Gen VI and beyond bring us.
I absolutely loved the originals when they came out, but when you look back 15 years, you come to realize that there were many bugs, glitches and flaws that make them nowhere near as good as today's games (technologically, at least). As for whether or not that makes them better, that's up to opinion.