I don't think the fact that their games are heavily based on stories is the problem here. It's that they can't tell most of their stories well, and that's putting aside the gameplay.
The storytelling was not well-liked for the most part because of the whole "illusion of free choice" problem. No matter how you got somewhere, the general outcome was always the same. Fallout, on the other hand, is not a point-and-click adventure game, but it nonetheless allows your character to be whatever you want them to be, which is more than your typical adventure game can say, and certainly more than any Telltale game can claim to be.
Now, as for the gameplay...from what I recall hearing about their gaming catalog, most of the games were considered too easy (Jurassic Park, among many others), with a couple of outliers that were considered too obtuse (Wallace and Gromit, of all things), with only their Monkey Island and Sam and Max games hitting the "just right" mark that satisfied both old-school and current adventure gamers.
