Remember when World of Warcraft did a 'Dungeons & Dragons' style video game which contained nearly all of the so-called virtual table top elements in it? They had utterly no monopoly.
Did everyone love Blizzard-Activision? I certainly hope not.
Did everyone get a shot at making a 'WoW-killer'? Lots of people did.
Did Blizzard eventually make it more and more crappy so that it went from 12 million players down to less than a couple million? Yes.
Is it impressive for a video game to run for 20 years and still have millions of players? Probably.
My point? If WotC didn't make horrid poop i bet they could do just fine without trying to scam a monopoly. What are they afraid of? Do they have a track record of making absolutely horrid poop more often than not?
WotC has released 50+ hardcover books for 5e. How many of them are amazing?
The jury rests its case.