I agree completely. While the case can be made that they have already gone there with how World of Warcraft has changed over the years, I think Diablo III is clear cut evidence that they have gone from focusing on making a great game (that lots of people will buy) to focusing on maximizing revenue at the expense of the quality of the game.
Diablo 3 is a hardcore facebook game designed solely to rake in money from a large user base, a dollar at a time.
Pretty much all the major design decisions feel like they were made not just considering the Real Money Auction House, but driven by the RMAH. They can carefully control drop rates and difficulty levels to control supply AND demand. They have made a game with a tiered difficulty which changes drastically. That in and of itself isn't so bad. But they have also made it so that you can negate much of that difficulty with sufficiently powerful gear which you can buy from the auction house. Farming gear directly to be able to progress is really kind of a dead end. If you need the gear to turn down the difficulty level, any gear you might get yourself (even if you are really lucky) probably isn't quite enough to get you to the next level. Your only options at that point are to grind endlessly for gold and items that you can hope to sell on one of the auction houses.