I just finished Fallout 1, it had been about a decade since I last played it. I'm now playing Fallout 2. They are great games.
But they aren't perfect. They have some big flaws, and they even have stuff I really dislike. I can take out a guy's best friend in Fallout, then ask him about it, and he gives me the same line as he did before. There were a lot of situations like that in Fallout, where I did something big that I thought would affect people's reaction, but they didn't change at all.
So despite the flaws, they are great, and so was Fallout 3. Yeah, it had flaws, but it also had strengths, and I'm not sure why fans of 1 & 2 need to tear it down.