First rule of fight club...
I'd say this is a HUGE understated problem in seduction, and you can see plenty examples here.
Traditionally (like evolutionary, instinctive based) guy needs real status to get laid.
Not fake bling status, but real, men follow you status.
That is the deep drivers of female attraction.
But in modern times, particularly due to feminism, which allows girls to slooze around without negative consequences, they can be "tricked' into short term attraction by using game.
This means lower tier dudes who never have much social status can learn PUA tricks to get laid.
Which is exactly what this guy did.
So he's getting laid, but he STILL craves social status, the admiration and validation of other men.
So he brags to other men about how easy it is to get laid (using short term tricks) in order to HOPEFULLY get the attention from MEN that he really wants.
The reason they are so quick to anger is they feel TRICKED by a BETA, which is essentially the WORST THING that can happen to any woman.
The modern PUA is very much like modern tech dudes (Elon Musk, that WeWork con artist, etc.) and VC's (and to large extent real estate goofs) who make tons of cash, but are not in the same class as old school empire builders.
it's very easy to FAKE your way into pvssy and money in modern society without having genuine, instinctive, subconsciously generated and projected STATUS.