I'll concede your point about not all illness being physical (although I find it hard to believe it's only 30%), but my point still stands if you replace the doctor with a surgeon.
So what? It's misleading. I don't know about you, but I wouldn't want to get surgery from a doctor and later found out that they had an MBBS in the history of medicine. Just like I wouldn't want to hire a plumber and found out they've got a certificate III in the philosophy of plumbing. If someone has a BSc I'm going to assume they have a background in science, not history and philosophy.
Just to clarify, I'm not saying it's not useful. Saying HPSC isn't useful because it's not a science would be like saying a law degree isn't useful - it is, it's just not a science and there's nothing wrong with that. I fully understand that history and philosophy are important - "Those who cannot remember the past are condemned to repeat it".