You need to remember that he is the GOAT. If he tells the club he is leaving....then he leaves. The club won't stand in his way.
Put simply, we are not good enough for him and we are probably 2-3 years away from being ready to win a trophy of any kind.
I made this point in the ETH thread: a lot of people on this forum are making out that he is the best manager in the World. He has not proved himself at a big club, where the pressure is much higher than at Ajax. The likelihood of his failure at MUFC is far higher than the likelihood of success. It is quite likely that he stays with us for 3 years and doesn't get close to winning a trophy during that time.
ETH will absolutely not tell Ronaldo to leave - ETH simply doesn't have the clout to tell the GOAT that he needs to leave due to footballing reasons. Jose, LVG could've got away with that....but not ETH.
Considering the above, if Ronaldo stays, then he'll do so, knowing that he won't be winning any more trophies. If I were Ronaldo, I'd go to a club so I could win another trophy next year. I would not stand for another season without trophies.
For selfish reasons, I'd rather keep our best outfield player.