So the person in question they are quoting left rockstar a while ago I don’t think he worked on RDR 2. So his info may be out of date. This could very well be true in his tenure when the PS3 was king of the hill.
I was going to post his video here but I didn’t think it added much to what people already know as I felt his answers were quite generic. However since we are talking about it here is the video in question
I don't need to watch that.
I already know why. It's because someone in the marketing/money department has calculated that they'll likely make more money releasing the PC version later.
There isn't any other believable reason.