Rationalmale said it best. For one persons sexual/life strategy to win, the other person's must fail.
All of TRP is setup to teach men how to shift the power more to their side. It also explains why this is better for you (obviously, but for more than just getting girls regardless) and even actually better for the women in your life in the end (most loose moral women dont care about the long run so they wont agtee with that part either).
That's bad news for the competition, both male and female. Women don't want to lose the obvious upper hand they have in regards to the sexual marketplace, and certainly not the legal system (family court for example).
Other men don't want TRPers using the info to get at their crushes, sisters, exgfs, gfs, and women in the mean time they hope will someday marry them (when they're done with the CC and ready to settle down and he realistic and pragmatic).
Why more of them don't learn it themselves to succeed, I have no idea. I have a friend that's had 1 short stint of sex go 3 months with a gf in his life. He's a decent average dork but not horrible. 30 yrs old. I tried to show him TRP and MGTOW. He tried for 2 weeks but said it was all too negative and that he would ignore any more links I sent him.
Personally I thought him being involuntarily celibate for a decade was pretty negative on its own.
I should note he was raised by a single mother and thinks his dad was a loser alcoholic (thats what she told him).
Edit: one of my major joys in life is getting girls enjoying talking to me at after work happy hours, and then slowly feed in the TRP pop culture stuff to where they ask "OMG are you one of those red pill guys??" And then watching them try to hamster how a guy they like can be 'one of those losers' they envisioned as a neckbeard in a basement. It has never stopped me from landing a girl that I already thought I was good to go with prior to mentioning TRP