This reminds me of nothing so much as the removal of St. Christopher from the canon merely because there is absolutely no historical basis to believe any such person ever lived. Fussy, fussy, fussy. At least Pluto exists. So he ate meat on Friday, once, for Cripe's sake. Is that any reason to decanonize him, if he asks for forgiveness?
I figure all those Soviet era artists employed airbrushing out Trotsky and other "non-persons" can find work airbrushing Pluto out of old text books and encyclopedias.
Well put.