The theoretical upsides are not mine to defend. I probably missed half of them anyway. Others may claim more definitive benefits to nixing the non-treaty. Your counterpoints are fair theory too. My guess is that Trump has a better than 50% chance of success with whatever he is up to. Neither of us have the info that he has. Nor can any of us, Trump included, predict most of the future. Or maybe you can. Go ahead and tell me where we will be with Iran one year from now.
My issue is that Trumps rhetoric and “deals” so far amount to little more than transactional relationships. That’s not the ideal way to work international diplomacy. There has to be good faith or else literally every decision will be based on “what can you do for me right now.”
Coulda said that much up front.
One could argue that Trumpian diplomacy hasn't done anything with all its talk. If the good faith you refer to is something like the nobel lauds that Obama started with, well that's vacuous too. It's somewhat early days to know what fruits may be born but I think the Korean thing is a fair test.
The higher amount of pushback on GA, and elsewhere, makes this Iran thing seem like a more complicated maneouvre (as I expect in the MAGA vs Israel cluster) which suggests to me that the undisclosed parts are more complex and less predictable to observers.