Its not just better rigs. Better propants, reservoir mapping, well placement, etc, etc, etc
As one analyst said this morning, E & P (exploration and production) is a misnomer, "there is no more "E" (exploration) We know where the oil is. Companies have gone from exploration to Manufacturing." Size and efficiencies will prevail.
https://www.cnbc.com/video/2019/05/02/core-laboratories-ceo-a-remarkable-boost-in-us-crude-production.html