As a poster above noted, maybe we are just influenced by what the video games have pumped out and added to make the game challenging for level 20+ characters (which are attained relatively quickly in these games).
Since I never played PnP Forg Realms I won't comment except to say that the other worlds (GH and DL) seem to have more emphasis on outposts and smaller towns with less magic and magical races (not that they aren't there, only you won't encounter them while going out to get your morning paper). Most of the potent magic belongs to few and certain spells like raise dead are much more rare. There also seems to be more strain between the races (elves being mistrusted and all that). And much of FR seems to centre on Drow which seems to be wearing a little thin.
Part of the Peril with forgotten Realms is that the same theme just seems to get repeated over and over in these video games. Not an inherant problem with the world, just the developers not stretching past the usual. I think the developers would do good to develop games centred on other worlds other than FR. After BG, they might have thought of going somewhere else with NWN.
However, I'm not the one putting up the dollars to market these things and it looks like by sales they are doing something right.