This is Iran's topography. In order to get to center of iran you are essetnially riding through valleys of death from which you can be ambushed easily from positions deep into mountains that are not possible to reach with bunker busting bombs. Add to that drones + mines and you have recipe for never ending production of caskets to who ever decides to invade them.
There is a reason why those guys are there before humans could even write.
From reports they also seem to spend last 50 years building vast underground networks and since they are oil state they had ton of money to do it well. Same reports say that their main operation hubs are around 1km underground same as Russian's, Chinese etc. Not even nuclear bombs will take them out.
If you can see their topography then you can also see that whole of strait is in reach of artilery fire from it's mountain range. If Iran wants to close straight it will close it and nothing you can do about it.
The best way to invade Iran is from pakistani side but that still gets you valleys of death just not as bad ones as with other routes but still you are looking at serious casulties.
Unless US is willing to commit mass of bodies and from looks of it no one has appetite for actual ground war in US there is no condition under which US can win this war.
Moreover the more time this war will go the better Iran forces will adapt to US hardware and strategies same way Ukrainians did. At start they were badly beaten but gradually over time they build up capabilities, tactics etc. where they could stop russians. Same thing happened in Afganistan. They were beaten, then reorganized, learned US tactics and started then to hears them, instead of using normal anti vehicle mines which humvess were pretty secure against with modification (in sense that crew can survive) they started to mass produce ied with any amount of explosives they want so they can adapt so not only humvess were being blown up but also apcs and other harder hardware.