[danparsonson]

The point is that you, dear reader, could be the Boltzmann Brain, and that would mean that all your memories spontaneously came into being, giving you the illusion of a past history, and it would also mean that you will dissipate again shortly after; there is no continuity, and we're not all BBs. 'We' are all just figments of your imaginary imagination, conjured momentarily into memory and then lost again.

For a Boltzmann brain there is no real past or future - your reality does indeed collapse immediately and you'll never know it; the idea that 'reality doesn't collapse immediately' is not a verifiable fact, because the only evidence you have to the contrary is encoded in and perceived by your brain...