The same art work representing a drawing of a man, appears in Grace and Frankie (2015) in the den of Robert Hanson (portrayed by Martin Sheen) as does in the home of Beth & Randall.
The slang in flashbacks is often not yet in use. In one scene set in the late 70's early 80's Rebecca answers an observation that Jack makes by saying "Right?" Which developed alongside "I know, right?" Both of which only came into use in the 2000's.