Natanz nuclear facility is rumored to be around 300 feet underground, much deeper than the tunnels in Lebanon. The standard US GBU-28 can go down around 160 feet and the GBU 72 can go through 160 feet of concrete and then deliver 5000 pounds. I think at this point the F15 is the only Israeli aircraft that is designed to carry the GBU 72 so all air defenses would have to be destroyed before it attempted this.
Natanz is pretty deep inside Iran and a one way trip from Israel through Syria to Natanz would be around 1100 miles. The F15 can do this but would need to be refueled on the way back. The F35 does not have the same range so it would need at least 2 refuels. Turkey, Iraq, and Jordan already said they won't allow aircraft from either country in their airspace so the refueling would have to be done over Syria, hence the reason Israel has been taken down air defenses of Syria, Iran, and Russia there.
The wildcard is what Israel's true submarine capabilities are, we know about their Dolphins but they are rumored to have nuclear powered though never confirmed. If some of those can get inside the gulf that would be a game changer