Remember that WGT courses are based on real photographs. That said, on those "CTTH only" courses, they shot less photos, just what they needed. Therefore, an upgrade to "full course" would require a new visit for (my estimate) a new full set of pictures and contours, implying negotiations and contracts and a lot of work and costs!
You are dead on with this analogy BUT...This has been WGT's "Excuse" for far to long now ...They need to "Find a way" There biggest competitor which IMHO falls short of WGT mainly due to where we are talking now... "The Forum" and comradery of members and all the our Country Clubs etc...Offers 39 courses just to start 19 official PGA courses plus another 20 of their own design...Then from what I am told there are another 1000 plus courses designed by players that are available for all to play?
At this point I would be thrilled with ANY course or courses WGT would offer even if they were just "made up" and designed strictly with all computer graphics ..Correct me if I'm wrong but Cabo and Whistler where both built without "actual" mapping photos? This is 2021 I'm pretty sure there are top computer software designers available (Maybe already on WGT's staff) That can pull this off?