I don’t think it’s clear that knowing we’re in a simulation “destroys” the simulation. This assumes that belief by the occupants of the simulation that they are being simulated creates an invalidating difference from the desired reference class of plausible pre-singularity civilizations, but I don’t think that’s true:

Actual, unsimulated, pre-singularity civilizations are in similar epistemic positions to us and thus many of their influential occupants may wrongly but rationally believe they are simulated, which may affect the trajectory of the development of their ASI. So knowing the effects of simulation beliefs is important for modeling actual ASIs.