This reads as extremely bizarre. I mean, reading the fifth amendment makes it pretty clear - no one should be compelled to witness against oneself. However, it looks like the current executive and judicial are thinking "well, those Founders were just idiots for putting such an amendment in, clearly it'd be much easier to prosecute people if we could compel them to witness against themselves, so why don't we just igno…
If there is a warrant to search my property, I am obligated to assist if required. E.g. open the gun safe. (Hey, speaking of guns...You know what other antedquated amendment from the Founding Fathers would be really convenient to ignore...)
Now, AFAIK, no one has tested whether that still hold true of a combination safe, where the access substaintivly requires information from the accused.
And a combination safe is very similar to an encrypted drive.