Exposing? Microsoft has made it very clear for a while that your Bitlocker keys are synced to your Microsoft account.

Hell, they even have a support page for it. Most of their support pages are nearly useless, but this one is even readable by a normal person.

And before someone mentions the part about Microsoft Support not having access to keys (because some smart ass always does for this stuff)… Just think for a second. Of course customer support doesn’t have access to the keys. What Support can do is not a limit for legal disclosure. A legal warrant (like used here) means they’ll give any info they have in a heartbeat.