I assume he was buried in a national cemetery...So yeah defacing,or otherwise desecrating a grave on federal land is well gonna be a felony.
He single handedly killed any closed fuel cycle in the USA and with it thousands if not millions of years worth of clean energy. No one man is responsible for a greater damage to the American energy infrastructure and supply, it is a crime against humanity as a whole and every future generation saddled with spent nuclear fuel vs abundant energy and only solid glass fission products that need to be buried for 300 years.
I believe with all of the SMR designs, we'll see the use of better fuel cycles which will include Pu production and fission. TerraPower backtracked on their traveling wave core concept and have apparently jumped over to the PRISM core. It looks like the others are setting up high burn-up cycles through the Pu chain.