What this phrase implies is that women dislike someone who is cynical. They apparently have accused the speaker of being cynical, of seeing the worst side of everything.
The speaker counters by saying that he is not cynical, just realistic or objective. He means that what he sees is really there, what he sees is realistic. He views things objectively, without prejudice.
The implication is that women see things from a kind perspective, giving others the benefit of the doubt, or, maybe, see things as they would like them to be or as they think they should be. While the man, he claims, sees things as they are.
Of course, seeing things in a totally objective manner is actually an impossibility. All experience is filtered through our senses and our minds, and none of us is truly objective.
What this phrase is implying is that there is something about women that makes them hate a person who is not cynical.
But I do not think that this is really what the whole quote from the book means. In the book, there is a part that you have left out. The whole quote reads
I'm not cynical. I'm merely realistic, which is something women can't stand."
When you look at that whole quote, what the speaker is saying is that women are unable to deal with people who are realistic. It is saying that women live in some fantasy world and they think anyone who is realistic is terrible.
Now that I look at your quote again, I realize that it's just a different translation from the one I used. But what I'm saying still stands. What's going on here is that the speaker is slandering women. He is saying that women are incapable of being realistic or objective.
But if you look on the whole content Homo faber is talking about, wouldn't you say he is just lying to himself? That he prejudges the women, by saying they don't like realistic/objective men? Maybe this whole quote isn't really meant as it stands their... Ofcourse he is also objective, but Faber is actually the definition of cynical? Isn't he?