PS3 was also selling and had new games (several crossgen as well) for over 2 years after PS4 released. TLOU and GT6 launched only on PS3 at the time and one of then was even after PS4 was launched basically.
The number of double dips isn't that much either, and if Pro didn't exist most would have bought vanila. Much more likely that a household have 2 or more switches due to portability and starting at lower price than another PS4 just because of Pro.
duduspace11 "Well, since we are estimating costs, Pokemon Red/Blue did cost Nintendo about $50m to make back in 1996"
Mr Puggsly: "Hehe, I said good profit. You said big profit. Frankly, not losing money is what I meant by good. Don't get hung up on semantics"
Azzanation: "PS5 wouldn't sold out at launch without scalpers."