Indeed, D&D marketing has always been very happy to claim their system does things - often to the point of writing whole sourcebooks about those things, like 'intrigue' - that it is in fact quite terrible at. This is by no means unique to D&D - WW wrote whole game lines that were absolutely not about the thing that the promotional material claimed they were about at all, like Aberrant - but it looms larger because of D&D's outsize market share.
Somewhat oddly for a relatively niche hobby, in the TTRPG marketplace there's a very significant sense that marketing is everything - that popularity is entirely dependent upon how cool the pitch is, how great the art looks, and so on and the mechanical solidity of a game is way, way down the list of reasons behind a game's popularity. Personally I suspect this has a lot to do with how very few tables play games anything like the rules as written and how a good GM can make a great game out even the most jaw-droppingly terrible of systems. Or, as freeform reveals, no system at all.