Are you denying that the Fifth Amendment only applies to witnesses (which seems clear from the text), or are you just disputing the court's decision that being compelled to decrypt a hard drive is not 'in effect' forcing someone 'to be a witness against himself' within the meaning of the Fifth Amendment?
"Are you denying that the Fifth Amendment only applies to witnesses"
Yes, because of the first two words of the entire amendment - "No person" that 100% excludes any qualifying status and grants everyone immunity from testifying in any effect against themselves.
