No, a mere failure to adhere to the Constitution is not in itself treason, as treason is well defined:
Treason against the United States, shall consist only in levying War against them, or in adhering to their Enemies, giving them Aid and Comfort. No Person shall be convicted of Treason unless on the Testimony of two Witnesses to the same overt Act, or on Confession in open Court.
And how is failure to adhere to the Constitution, or (in this case) openly trashing that very document you have sworn to protect, not an act of open war against the USA and/or adhering to the USA’s enemies? especially by one that holds such a high office as SCOTUS justice? Don’t forget Article 6 Section 3 of the Constitution as well.