I don't, but it's not quite as simple as it being worse.
Colonization 2 seems a little confused in how it is constructed. If it had been a straight up graphical update, I would have been happy, but it's not. If it had been a proper sequel, rebuilt from the ground up, I would have been happy too.
The problem, as I see it, is that it is a remake of Colonization 1, with some changes. Some are good, and some are bad. Some are just buggy. But there's not enough.
I enjoy Colonization 1, but while I do honestly think it had fewer things wrong with it than Colonization 2, I am fully aware that my enjoyment of it comes through nostalgia. If I had never played it before and sat down to play it today, I probably wouldn't like it. Games have come a long way since its release, and there's not enough there in the first game for it to be commercially released today.
As such, when I play the original, I lower my expectations, and forgive the bad graphics, the bad AI, the lack of multiplayer, the hoops I have to jump through to get it to run.
If Colonization 2 was just a graphical update, I could still do that, though anyone who had never played the original wouldn't see it that way.
But it's not, so I come to Colonization 2 looking at it through the same eyes that I use to appraise games like Team Fortress 2 or Red Alert 3. What I see is a game with too few features, and too many problems.
Colonization 2 falls right in the middle when it comes to being a sequel. Too much changed to be a simple remake, but not good enough to stand on its own as a game released in 2008.
It failed to meet the expectations of my inner seven year old, and it failed to meet the expectations of my outer twenty year old. Which is a damn shame.