That's fine, here's mine. I was excited for Halo 2 because I loved the way Halo CE played-- both in campaign and multiplayer. I didn't care about Guilty Spark or Master Chief or any of the characters as the plot was only a device for level and encounter design to me. 2's Xbox Live popularity was one thing, but the clout CE originally garnered and what it did for console splitscreen/LAN parties isn't one to be discredited. I don't think it's a stretch to say that Halo CE was a popular game, and it was also well known for its multiplayer component; which is something you claim the pistol shouldn't allow.
However this will go nowhere as there's nothing either of us will legitimately say about the connection between utility weapons and the respective popularity of the titles. The pistol is simply not OP because all the options were powerful, the shotgun and rocket launcher were also some of the most ridiculous versions of those weapons as are the grenades.