So, one guy has tens of extramarital affairs and is considered a disgrace, someone who must come clean and ask forgiveness. Another guy has hundreds if not thousands of affairs, in the process acquiring HIV, thus exposing his poor wife.
Which guy is morally worse? Clearly, the guy who caught HIV by having 100x more affairs. Yet, when Magic Johnson announced he had become HIV positive due to innumerable extramarital affairs, all he got was sincere pity, poor Magic. In contrast, the venom inspired by Tiger's actions is rather severe.
To me this highlights that everything has a context. What is true, just, beautiful, or important, is rarely seen in isolation, but as a member of a larger class. Magic was announcing he had HIV when the politics of AIDS were especially large, and 'blaming the victim' was not politically correct so he got the appropriate pity, regardless of his reckless behavior. Tiger doesn't have any such angle.
The importance of context is why so many partisans think the other side are a bunch of hypocrites. Your average true believer rationalizes exceptions to their world view, sacrifices various smaller principles to larger ones. This is the right thing to do, just as murdering Hitler is morally good thing to do if you had a time machine, and saw him in 1938, or ignoring Pasteur's faulty argument's in favor of his 'germ theory' would have been prudent.
The key in all these exceptions is being on the right side, which is determined by current politics, posterity, and one's own conscience. Clearly, the easiest way to go through life is to see what is popular, and shade one's prejudices appropriately, so 150 years ago it would be proper to be a racist and think that the 'upper class' was a thoroughly different beast, whereas today smarmy college freshman at top colleges think every human grouping possible has equal genetic ability and interest in every meaningful human dimension. People never get rid of their prejudices, they just change them.
It is far better to acknowledge our most basic unproven assumptions than to claim they don't exist, and that it's all about truth now, or only 'my side' is using science (the other, driven by crass self interest). Of course it is about truth, but truth of what? No one lies like the indignant because they feel their big point is being obscured by unfair tactics, and so feel justified in fighting fire with fire to acheive their ultimate, good aim (which, because it is good, is also true).