Professor Stephen Johnson says, yes. His article is “The Changing Discourse of the Supreme Court,” 12University of New Hampshire Law Review 29 (2013). I correlate this decline in readability with the increasing density of law review articles. The top law review officers go on to clerk for SCOTUS and bring their bad habits with them. Here is the abstract (excerpts):
Academics, judges and other commentators complain that, for the past few decades, the Justices on the Supreme Court have been increasingly...