I don't disagree that Iran could make one quickly (miniaturization would take a bit longer though.) I do disagree that they're already making one because they've had this capacity for 20 years now. 2002 is when they performed the implosion tests:

https://www.washingtonpost.com/national-security/iran-nuclear-bomb-design-capability/2021/05/14/a47e75cc-b4f8-11eb-ab43-bebddc5a0f65_story.html

As of now Iran benefits more from threatening to cross the line that it does if it actually crosses it. Iran is hoping to leverage the threat to get a better deal. Maybe that won't work because of their support of Russia in the Ukraine War. However, that's what they're likely doing. If they cross the line then they likely get attacked by Israel, KSA and the US as well as max sanctions, embargoes, blockades, etc.

I highly expect Iran to state they'll be converting the TRR back to using HEU (as per its original design) instead of LEU. Then they'll have a legitimate reason for needing large quantities of weapons grade uranium. This puts them as close to that line as possible without crossing it.

If Israel, the US and KSA attack then Iran will make a bomb immediately and detonate one in the desert signalling the attacks are an existential threat which they'll respond to with maximum force.

The benefit of the JCPOA wasn't that it prevented Iran from having the know-how to make a bomb, it was that it ensured all the monitored uranium wasn't diverted and that it was converted to fuel rods (or at least stored in UN monitored containers/locations.) It also gave the IAEA broader ability to monitor for a parallel program.