That thesis is over-reaching. What I would say, though, is that D&D has such market penetration, it's become like kleenex: the uninitiated cannot think of the c

That thesis is over-reaching. What I would say, though, is that D&D has such market penetration, it's become like kleenex: the uninitiated cannot think of the concept of a TTRPG without thinking of D&D. While other TTRPG's are still free to exist, it is much harder to convince a new player to hop on board with anything else (or to even explain to them how there are games very similar to Dungeons and Dragons that aren't Dungeons and Dragons). It doesn't help that things like the term "DM" are patented by WotC, too.