Passwords/passcodes are not protected under the First Amendment, they are not considered speech. They may be protected, as a key on a keyring, under the Fourth or Firth Amendments. But those same amendments provide for a legally obtained warrant, if there is enough verified evidence in support of probably cause, to legally justify such a warrant.
If it's a legally obtained warrant, based upon valid proof of probably cause, negating the Fourth and Fifth Amendments, as the Constitution does provide for a legally obtained warrant.
Calling it speech is just a way to try to muddy the waters and make the issue unclear to the masses, in the hope of getting support from those who have never read the Constitution or researched the legal precedents regarding these issues.