You are a little out of date, sorry.
Oakmont has been back for 2 years, after a 2 year or so absence due to a licensing (think money) dispute.
As to Cabo and Whistler, I agree with you totally. WGT never owned those courses. TruGolf did. Why WGT and TruGolf could not reach an agreement to continue those courses is over my pay grade.
If WGT worked a deal with TruGolf and brought Cabo and Whistler back into play, we would not be complaining about lack of new course for 2 years.
(It is also possible that TruGolf has those courses operating on other formats that I don't play.)