I suspect kill decks will flourish when corps are strong, because Runners struggle to spare slots for luxuries like Plascrete when they’re fighting for every access. Right now, Runners are strong and the luxuries are back. Deus Ex is going to get slotted again too, soon.
I think you should never run a pure kill deck. What makes a lot of supermodernism decks so scary is the threat of the score.
Sam played his Mushin/Gird version at Nationals too.