Instead, let's say I froze my brain. My brain that makes me me, stops working. That makes the thing that is me cease to exist. The continuity stops there. The person that you revive 200 years into the future may have the same state that I left with, but it wouldn't be me in the sense that makes you want to preserve "yourself" via cryonics in the first place. It defeats its own purpose.

How do you know that?