This is simply not true.

Iran's religious dictator issued a Fatwa declaring nukes haram. This is why they've consistently stopped at 60% enrichment.

In a religious cult, everything rides on the leadership. He can't just come out and change his mind. He must have a very definitive reason that doesn't disagree with the reasoning in the previous Fatwa. His only real out is an existential threat where threatening a nuke becomes a tool to preserve lives.

Israel and the US have now given him that out. It remains to be seen if he actually takes it.

That Iran has been "full-tilt" pursuing nuclear weapons for decades doesn't make sense. Building a nuke isn't that hard, and getting the nuclear material is the hardest part. They've got that worked out. They've had the capability to do so for 20 years now. I defer to the intelligence community; they have the capability to build the bomb within about a year if they chose to do so, and are also not actively attempting to do that. (Until a few days ago at least).

If Kim can get nukes, Khomeini can gets nukes.