Maybe they were far from implementing modern nuclear weapon designs, but there are simple applications like a https://en.wikipedia.org/wiki/Gun-type_fission_weapon delivered by ground. With that approach the bomb assembly is pretty straightforward engineering once they have sufficiently enriched uranium (which they already did the bulk of the work for).
Regardless of whether any past claims were misleading or what not, today noone disputes that Iran has a large stockpile of 60% enriched uranium, and is officially in breach of their NPT obligations per the IAEA board.
Here it‘s less clear
https://www.bbc.com/news/articles/cn840275p5yo
Sound more like Musk‘s „FSD is ready next year“