Although i think they mostly recognize it as customary international law.

Nonetheless international law isn't really worth the paper its written on. The bigger thing is there are a bunch of other countries dependent on the strait that might have something to say about it.

Trump could easily agree to it and consider that “their problem”. (I think Iran realize other countries have a say as well.)

It's interesting that these days any treaty that the US hasn't signed is probably a decent one, especially if hundreds of other countries have signed it.

It's usually the US and a bunch of garbage regimes on these lists, I guess there was a message being sent over time.