You really should take a look at the post strike pictures,as these show very clearly the level of accuracy that was involved in the strike,this was literally pinpoint with a likely cep in the low single digits,the iranians could`ve hit literally any single part of those facilities that they wanted to,any structure at all.
In addition tho the us personnel would`ve been in their bunkers and shelters on full alert,the us early warning systems in the region plus observation satellites would`ve also been watching iran and the known facilities and bases for any launch indications,so they would not have been taking any risks either.Because once people start dying it becomes much,much harder to lower the tensions politically and militarily,you then have the very real risk of an escalating series of tit-for-tat strikes that could easily spin out of control and into a war,and ultimately no one wanted another war in the region,not the us,not iran,not the gulfies and not even israel.Thats why when it came right down to it iran was careful with its targeting,thats also why trump despite his prior dire threats of launching a massive attack on iran if there was ANY retaliation for soleimanis assassination instead sounded far less bellicose and far more conciliatory in the immediate aftermath of the attack.
Ironically probably the one thing that all the players in the region could agree on is that they dont want another war in the region because they`d ALL have a lot to lose.
If the iranians were really the "cowards" that you seem to think then why didnt they simply agree to all of trumps new demands after he left the jcpoa and simply save themselves all of this bother?.