I have never really looked into de Sade but I expected to reluctantly like and respect him. Not so it seems though - there are his madly irreverent early letters that really are charming and funny but his adult character is not exceedingly pleasant. Of course his actions are mostly nothing to object to if between consenting adults but concent in his 18th century context is really dubious, or largely non-existent, and no matter how rotten the society, he largely accepted it apart from some ideals mostly practiced in breach or in theory. Sexual fantasies are in any case usually best left unattempted in real life - they easily become ridiculous and/or unpleasant or worse. His certainly did, and not really awfully ridiculous at their worst.
His thinking was better and in some respects refreshing (as against the disgusting cant of this particular age, one of the more horrible eras) but even there he resided much in his own solipsist unreality (though creating some rather effective pornography in the process). So I suppose he too was deceived and betrayed but surely not nearly us much as his paid or even forced partners, those much truer victims of that cruel, sadistic age. And that cruel, sadistic person, however irreverent of the pretensions of that awful era.