editorialized torpedo

True. We aren't supposed to unironically or sincerely support any principle the Seven creates, develops, or endorses and it is the only religion in the entire known universe that has no "miracles" or magical ability to given/performed by any of its followers. I don't know if the institution and the religion itself will be destroyed. Because even if the Sistine Chapel or all the bishops, priests, nuns, etc. of our own world were mysteriously disappeared, there'd still be the worshippers and their memories and historical records of cathedra, Romanesque, etc. building plans, etc. Catholicsm would still exist, so the Faith and this miracle-less religion and the concept of the Seven gods themselves would exist of the Sept of Baelor and other important septs were obliterated. As for the Citadel (THE maester hub) and home to the grandest library of the Seven kingdoms, again, as long as people have their memory and some other records the maesters kept in various houses as well as copies of certain tomes, they can restore some measure of a "Citadel".

Now will there be some sort of destruction done against either the Citadel or the KL Sept? More than likely, esp since we still have all those casks of wildfyre Cersei is storing. If/when Dany ever makes it to KL and Westeros, she'll still have to contend with followers' anti-magicsm and xenophobia. And even if she becomes the Queen, most of the Seven Kingdoms, peasants and nobles, worship the Seven. A lot of villages have some sort of access to a small place of worship, if they don't already have designated spots. I don't think this religion will be eradicated anytime soon.

Aerion "Brightflame" Targaryen is the only Targ who drank wildfire and believed he could literally become/transform into one.

Aerys II became obsessed with wildfire once he realized how vulnerable he was against rebellion (Battle of the Bells and the Defiance at Duskendale) and would later surround King's Landing with it in a mass murder-suicide if threatened. Wildfire, to him, was an extension and mimicry of using actual dragons, showing his desperation for power. Aerys II's regard for wildfire was more metaphorical than it was for Aerion. He was still insane, though, like Aerion. He was of the paranoid sort, gone to a place of no recovery from him believing he would lose power at any moment after years of trying and failing to sire children.

Other Targaryens like Aegon IV, Aegon V, & those at Summerhall, used wildfire while sane. Not to "become" dragons but just use it as a simple device. There was no madness and no twisting wildfire to be something that it is not, at least not any twisting that was itself not a an experiment made from measured logical conclusions. Aegon IV for warfare. Aegon V, Maester Corso, Duncan the Tall, and Prince Duncan all wished to restore dragons by using wildfire to heat up and “activate” some eggs that never hatched. Even Aegon III and Viserys tried together by bringing in some sorcerers and the like from Essos (though not with wildfire).