The problem with BS against Sifr is that BS’s relative immunity to getting its ice blown up by Parasite is one of the big perks. Sifr means Parasites are automatically live, while also making it dangerous to leave ice rezzed. Derezzing those ice to protect them costs you credits and clicks and eats into the natural advantages of BS.
I think if BS is going to survive, it needs hard-to-break ice that are awful to facecheck, behind ice that the Runner wants to Sifr. It’s like the Dumblefork days, only worse.
The only saving grace is there probably aren’t any decks that want both Aaron Marron and Sifr. Which means deckbuilders need to choose between free-rolling CTM or freerolling glacier. I myself have just gone back to CI7 in disgust.