I think the only thing that is certain is change. Our practice will be different twenty years from now just as it was twenty years ago. While nothing is impossible, the death of anesthesiology as a specialty is very unlikely.
More likely is that we will be paid differently than we are today. Instead of billing for start up units, time and sick patient modifiers, we will be paid for outcomes. Some of these outcomes will be silly and impossible to comply with (temperature) and some will be very reasonable (time outs, timely antibiotic administration).
Technology will change our practice. Forty years ago, anesthesiologists noted "bright red blood on incision" as part of the anesthetic record to document oxygenated blood. This is never done today because of the pulse oximeter. Unrecognized esophageal intubations are extremely rare due to end tidal CO2. There are technologies that have yet to be invented that will revolutionize our practice - we just don't know it yet.
Those of us who, for better or worse, embrace change will always be valuable and will always be compensated.