I have read book 1, 2 and parts of book 3. This was a couple of years back and honestly, what nipple-flip is talking about have made me re-consider the value of those books.
When I first read them, especially book 1, mentally it felt like I was shattering old perceptions on intergender dynamics. And to some extent I feel that it was necessary to do so - but if it was the best/healthiest way to go about it, I'm not so sure. Mainly because, like nipple is talking about, you can find your self viewing women as something other than human beings, as weird as that sounds. Like creatures that almost conspire against men on some emotional level etc.. Idk.
For what it's worth I've left behind reading most RedPill material, like the subreddit etc, simply because it wasn't really adding value to my life in any productive way.
Discovering Andys blog and this forum has been 1000x more helpful in terms of actually improving my life/mental health/understanding of women than reading The Rational Male did.