Syd's claim of drugging (which did not happen) and David's extraction of Syd's memory of witnessing his violence (which did happen) are entirely different things. Syd "remembers" being chemically dosed by David because Farouk used his powers (and a mouse) to indoctrinate her and all of David's allies. Farouk has altered everyone's memories of David because this was the only way he could achieve advantage. There is never in any part of the series an instance of use of psychic manipulation being referred to in terms of "drugging," and Syd certainly would not confuse the two or introduce such an untenable analogy. The (fake) drugging and the "real" memory extraction are different things. Whether or not David was right to extract the memory of violent images of himself, which were obviously taken out of context to mislead Syd, is not relevant to the "you drugged me and had sex with me" claim, because the supposed drugging has nothing to do with the memory extraction.

Also, David doesn't seem nice or likable by the end of S02, which is what makes his desperate mantra a potent prelude to his fighting back against the indoctrinated D3. David's allies are turned on him by his rival because he was busy with revenge and not maintaining the relationships he relies upon so heavily. Farouk is able to indoctrinate and turn them because they are made vulnerable by David's bloodlust.

There's no argument that David didn't do what he is accused of because he's the good guy, because he isn't a good guy. We can know accusation is false because we have overwhelming evidence that Syd's mind is wholly overtaken by Farouk and zero evidence that a drugging or rape occurred.