It's a cyclical event. It goes up and it goes down, then it goes up again. Most things go this way.
In the eraly 1970's emissions was the killer. Personally, I love to be behind an old car with zero emissions for the memories that odor brings back. Sure, I don't want to STAY behind that car. High insurance rates on muscle cars was a contributor, and then the gas shortage and high fuel prices was the nail in the coffin. People started buying Datsuns and Toyotas as they got much more gas mileage than a Pinto or Vega.
The manufacturers are in a better position this round. First of all the mandate doesn't go into effect until 2020. This is much more time than the era when the catalytic converter had to be implemented. Also Ford already can build a V6 with 425 HP and a 4 cylinder with 250 HP and both get better gas mileage than the V8 and V6 they replace. The EcoBoost engines are going to be very welcomed. You are also going to be surprised by the turbo diesels. They're not your Father's turbo diesels.
If you don't want to change with the times then do what I do in this case, as far as hvaing the kind of car you want goes, not necessarily a daily driver though. Pick out which car, at present, is the one that you've always wanted, get it, and build it the way you want. Then you will always have your car and drive it too.
My wife has her "last" car that she REALLY wants, her 1966 Mustang. She's living her dream with it. I have my "last" car, my Mad Max Interceptor I am building, MY dream car. We are set for life.
Steve
Steve