I'm not sure though if Donaire is thinking retirement, I never heard from him telling the public about his plans. Even after Inoue knock him out, he still want to chase greatness at 115 lbs against Estrada, but now he chance his plans.
He still wants to fight, but I believe he mentioned that he wants to retire as a champion, so he would like to get a belt again, and with what happened. I don't know anymore if Donaire can still have a championship fight soon, seems like the chance is not fair for older fighters nowadays.
But right now, the opportunity is there so why not take it.
But he cannot wait longer, he needs to be active to have more fights and to test himself if he still can dominate in this division.
I haven't seen a boxer who quit on top though, I mean if he becomes a champion again, I doubt he will just say's no I don't want to fight again. So obviously, it's up to the result of his next fight, whether it will be against someone like Rodriguez or Gaballo.
2-3 years might be quite long enough for his career, he is already 40 years old, and once a fighter reaches that age, sooner or later his body will be very different because of the effect, the wear and tear of being in this business for many years.
You are right, there's a lot of opportunity when you are a champion, so why would a boxer retire? It doesn't make sense, if he does really say it, then I think he has a different mindset, he values his achievement more than the money he will potentially get in future fights. Of course, there are boxers who retires during their peak, just like Mayweather.
If he retires then he might lose millions of dollars in the bag since he cannot get that anymore if he decide not to take fights. So I think what he did right now is a smart move since while still he can keep accumulating while there are still big offers to you and he can make his future more secure with that. Maybe its better for OP to close this thread now since Donaire vs Moloney is no longer happening and there's nothing to discuss about more further updates regarding this match.