Nope, Inoue already has established a good name and he has been mentioned by several boxing legends and some active boxers as well. Whoever Inoue is facing it will always going to generate a good money because the boxing fans would come to see Inoue's performance.
A boxer who have an excellent skill sets can be easily become popular that will attract boxing fans.
While he could generate a good amount of money, it doesn't compare to what he could make in the higher division. We can take a cue from the experience of Pacquiao. He was already popular in the lower division, but he didn't earn the same kind of money until he moved up to the higher division.
Of course, the higher the division the higher the paycheck. But it really depends on his body, on how far he can get his frame. Maybe 130 lbs might be huge for him though. Not sure if he can fight on that weight class, but let's see.
Even though that Manny has laid down the blue print, Pacquiao is very different though, I mean his genetics might have been breed for sports not just boxing. But his frame, his legs and that calves which generates power are one of the key for Manny's success and I doubt that anyone can duplicate it.
Inoue does have a strong spine that can carry weight. It just needs weeks to months to get used to it as long as it's gradual in adding weight, it will not be a problem for him. The fight schedule gave him enough to prepare.
Het gets a title shot in this division and then claims it. He then can move to the higher when no one challenges him after it. This is what he is after I think, he is already a top p4p fighter now he needs to claim bets in more divisions.