Revisionist history here.
On the occasion that two event producers compete for the same dates on the WPA calendar, the problem of assigning the dates belongs to WPA.
To you, an event producer can choose any dates for their events but in practice, there are many issues that sometimes get in the way. In Matchroom's case, they have one issue that nobody else has, and that's the television issue. No, they can't just walk up to Sky Sports and dictate the dates on which they'll broadcast. Sometimes, they have very few options and have to work around the time slots which are available to them. Would you have them forego a chance to televise just to get out of the way of some other event, or to make the WPA calendar more player friendly?
To you, Matchroom deviously plans to compete with or obstruct other event producers by scheduling the way it does, and you couldn't be more wrong.
Finally, non-WPA-sanctioned events are not relevant here. Nobody is going to pay too much attention in their event scheduling.
Bottom line is that unless you run a WPA sanctioned event, no date protection of any kind should be expected. Is it a little unfortunate that the $325,000 prize fund World Pool Championships (which will pay out $100,000 more than what was paid out at the World 10-ball) coincides with the $10,000 added US Open 8-ball and the $10,000 added US Open 1-pocket.
The primary incentive for a major producer to avoid scheduling over any non-sanctioned events is that doing so could cost them access to a few top players. Case in point is that reigning US Open 9-ball champion Carlo Biado chose to skip the World Pool Championships.
Matchroom has conducted its business responsibly here.
