That's not it. If it was a AAA 1st party IP it would have flopped. No DnD is an excuse as to why Sony tentpole games don't sell well. There just isn't a market for them on PC.
Seriously, what difference does a release date make? It's a brand new game for you. Not only that but if you were interested then the hype has been building for years, making the purchase even more likely.