Well, I'm not sure if it is that dire. Money-spinning move, yes, but it is not as bad an option as say, PSG. With Juve, now the league is getting slightly more competitive too, and he has a better shot at Europe there than with PSG. Plus, he can learn more with Chiellini/Bonucci there too. And playing with Ronaldo is an obvious attraction. Admittedly, the only other feasible options were United, Liverpool and Barcelona - he wouldn't be a guaranteed starter at Liverpool/Barca and I don't think any of the three clubs could afford the wage anyway.
Not saying he hasn't moved for money, but you have to see that he has some positives too at Juve.