While Drizzt does take direct action and shows up with alarming frequency (seriously, he is like the Wolverine of Forgotten Realms), I personally think the biggest offender is the sheer quantity of lore instead of any one character.
I've literally been a player and watched a DM try to set a game in Westgate. He made up a fictional thieves organization and had no idea about the Night Masks, Fire Knives, or the Grandmaster of Assassins. And if they were not around, was King Dhalmass and Queen Jhalass still killed? Etc. Or another game set in Phlan where the DM didn't know anything about the influences of Zhentil Keep, the history of the city, or even the layout of the city which one of the players had memorized because he loved Phlan from the Gold Box days and the Pool of X Books.
There were a lot of things that could have been done better. The DM could have spent more time learning about the setting, or the players could have settled down and let the poor guy just run the fun game he wanted to run. But I've seen this happen in literally dozens of different forgotten realms games other people have run. Some groups handle it fine. They don't even care. It's not an issue for them. But in other groups it does become an issue, especially for DMs or Players who know a lot and have pre-existing expectations for how places are or people act.
I wish it didn't happen. But it does. My solution was to avoid the issue entirely and play homebrew.