Was Spectre as it's understood today ever enunciated though? Not being combative, legitimately looking for papers here because I've read a lot of ones that talk about using side channels to break kernel security [1] and observing that branch predictions are shared (and themselves can be leaked cross context), but never an integrative approach until the Spectre papers dropped. IMO it's one of those things that is so painfully obvious in retrospect but that was a sort of odd blend of works at the time.

[1] https://dl.acm.org/doi/abs/10.1145/2976749.2978356