It feels bad seeing legends getting mauled by younger fighters that they should've beaten during their primes. And it's the same when stars from other sports like the UFC cross over just to get exploited and destroyed for money. I cannot blame them though especially if the amounts offered are life-changing to them. They would rather take a punch from Jake Paul and get shamed for millions.
Imagine Jon Jones' rematch with Cormier with a PPV buys of 800k. His guaranteed purse of $500k ballooned to around $2m. But that PPV buys figure in boxing at that same time would've guaranteed an easy minimum of $20m payouts for all the fighters in the event. It's funny when some people tried to defend UFC contracts and purse sharing, especially its stars.
I can not blame them aswell, people have a different perspective on this that Jake Paul should fight a professional boxer instead of fighting retired MMA fighters, the misconception of Jake Paul is not really a legit boxer is still there so fighting a boxer would just maul him down so for the fight to be fair he would get an MMA fighter not just an MMA fighter but a retired old MMA fighter to his advantage and people are saying he should fighter YouTubers aswell than gnashing his teeth with some MMA fighter because of this I was to see a KSI VS Jake Paul fight, or Salt Papi VS Jake Paul fight, that will be a great fight to watch,
I really like the fighting style of Jose Aldo, I still remember those fights against Conor and some other great fighters, and for sure he will be a great element in boxing, I can't wait to bet on him again.
As you mention they always have the option to live from coaching, or become a trainer, but that's not enough money for someone who already gets paid as a UFC champ. So, I'm sure money is the motivation behind that decision.
The Problem is Jose Aldo is not in his prime anymore he would just lose to younger fighters inside the ring, but the legacy that Jose Aldo leave in the scene of the UFC or MMA world really has a great impact, seeing the fight of Marlon "Chito" Vera when he fought Jose Aldo it becomes a life-changing experience for him, he now is using the style of Aldo in his fights, not all because he is mixing it with his own style but that lost from Aldo has become an inspiration for him instead of a downfall, Pedro Munhoz also has that tendency of copying some of Aldo's technique that boxing style of Aldo is one of the best and effective in the industry he is one of the great strikers in the UFC, no I think he is on the top, even though he is not in the UFC anymore you can look at those fighters can you would notice some shards of Jose Aldo in them,