Something better came along. In our current case, that was more technology for the same product and accepted higher prices.
If we were on the same technology and pricing of the 1990s, our production rates would still be falling.
That is what technology always does. I was arguing this same point in the 90’s with people demanding government intervention in energy policy. It was true then and it is true now. The government needs to stay out of the energy business and let technology and economic pressures do what they do.