Mileage awards are getting more costly to use but miles are easier to accumulate. My own sense it that this tends to balance out. The article doesn’t even mention increased award opportunities that stem from airline alliances and opportunities for non-travel awards. A similar story with more details on award price increases can be found here.
Obviously the revealed preferences of consumers — the fact that programs drive spending behavior — suggest that people believe there’s still alot of value in loyalty programs. Nearly half of all Americans carry credit cards tied to a loyalty program.