First, you've crossed over from criticizing delivery into criticizing content, so it's clear that's actually the part that offends you. What you're saying is that Damore shouldn't have delivered his opinion unless it was first made to match something reasonably close to your own opinion. There is nothing inherently "dishonest" or "perverted" about Damore's memo; that is a subtext that you are choosing to read in because you disagree with its conclusions.
If Damore had pined on the tragedy of the modern economic structure while exhaustively disclaiming every potential discriminatory implication before he began the memo, I guarantee people would've read just as much "intellectual dishonesty", "perverted reasoning", and "loads of bias" as they did now. In fact, they very likely would've read more, taking the content that initially appeared friendly to their POV as a sign that Damore had malicious intent and that he was attempting to hoodwink people by pretending to be "on their side".
As discussed below, if someone wants to dismiss something they don't like, airy, abstract terms like "perverted reasoning" will get bandied around no matter what. These terms are great precisely because their subjective interpretation allows the writer to sound semi-credible in their condemnation without having to specify further.
Damore was fired because once this hit the mainstream press, it was the only way for Google to preserve a strong defense against inevitable discrimination suits.