The "fiat collapse" can only happen, if there are enough people (regular people) using Bitcoin, thus forcing states/institutions to also use Bitcoin.
Majorities of voters (motivated by their incentive to preserve the utility/usability/legality of their Bitcoin holdings) will have to basically force pro-Bitcoin policy.
Otherwise, institutions/states won't be under any pressure to even care about Bitcoin. They'll just happily continue using fiat currencies as a tool to get more leeway for setting policy.