Again, I'm not trying to argue this on its merits. I just was surprised by your wording, because I got the impression that you took the matter as settled, when it is very contested.
what you fail to realize is that this is manifestly a contradiction: by definition if it were more socially acceptable to discriminate against "white males" then white males would be the marginalized class. that's why claims like this are farcical; of course more people are fine discriminating against black people and women!
On the other hand, I fully concede that, for my history and CS dual major students, I'd agree that it's be a bad idea to get a PhD in history if you have the skills and inclination to get a CS degree or a job at FB/Google/etc instead.
Objectively speaking, if you spend five to six figures on a degree with a 10% chance of landing a job through it, that's not an attractive proposition.
"Futile" may be the wrong word, a better word would be "foolish".