Are you unbuttoned?

No buttons to unbutton today

Wouldn't the modern term be de-velcroed?

Don't have anything on now that needs unbuttoning

Nope...only unhinged

Nope and clothes ain't either cause I'm naked.

Yes

My shirt is, I'm comfortable.

Immediately, "The unbuttoned mind of Bob Newhart" came to mind for me. If he is the old model, then I am unbuttoned.

Elastic waist pants no need to

More like unhinged...