First, Phil has cash flow issues no matter how big or small his betting habits are. He didn't pay his caddie and he had to sell his jet. Yes, the kids are still eating we all presume. This is why the Saudi tour and $$$ is attractive.
I have attached the 2019-2020 player rules handbook for PGA Tour members. (I am sure they have not changed much). First of all on page 127 you can see that players are explicitly forbidden to play on conflicting tours without approval and there is a laundry list of what is needed for approval. The Saudi tour needs approval from everyone on the PGA tour as well as players that are members of both the PGA and DP tours. This requirement is not something new like claimed earlier in this thread. Phil as well as all players knew there would be issues. This discussion that the DP tour might not come down hard on players like Sergio might be true but Sergio is gonna have PGA tour implications since he is a duel member.
Second, Phil made some horrible comments about the PGA tour leading up to the release of his comments by the author. Those comments are in violation of another PGA tour player rule. You cant talk bad about the PGA Tour. Until Phil clears the air and falls on a sword, he is not likely playing in the PGA Championship. It's not happening. That puts Phil in a tough space, he would have to have a press conference prior to the PGA where he takes back the negative stuff he said about the PGA Tour but at the same time answers questions about playing the upcoming Saudi Tour.
PUBLIC COMMENTS, PUBLIC ATTACKS The favorable public reputation of PGA TOUR, its players and its tournaments are valuable assets and create tangible benefits for all PGA TOUR members. Accordingly, it is an obligation of membership to refrain from making comments that unreasonably attack or disparage others, including, but not limited to tournaments, sponsors, fellow members/players and/or PGA TOUR. Speech that could be reasonably viewed as hateful, abusive, obscene and/or divisive is expressly prohibited. Responsible expressions of legitimate disagreement with PGA TOUR policies are not prohibited. However, public comments that a member knows, or should reasonably know, will harm the reputation or financial best interest of PGA TOUR, a fellow member/player, a tournament sponsor or a charity are expressly covered by this section. Any violation of this section shall be considered conduct unbecoming a professional.
As I mentioned earlier, I know a number of people that work at the PGA Tour. If Phil wants to play in the PGA he needs to clean up the mess he created. If he wants to play on the Saudi Tour then we will likely never seem him in a PGA event again.
Do I think its right that the PGA tour is doing this? Read the player handbook and see how important it is to them to have the best players at their tournaments to support their sponsors. If that stops happening, the PGA Tour falls apart. That is why they will go down swinging.