How much do you know about research funding? For example, the fields you mention (sciences/engineering, medicine) pull in vastly more money that humanities. Be

How much do you know about research funding? For example, the fields you mention (sciences/engineering, medicine) pull in vastly more money that humanities. Because they have more money, they hire more faculty, and they also train and graduate more PhD students. I knew a few humanities PhD students while I was in grad school, and none of them were funded by research grants. If they were lucky, they got fellowships. That's a stark contrast to engineering where both grant and fellowship funding was relatively plentiful (though I've got a few horror stories there too). On top of it, humanities jobs are really hard to find (even more difficult than fields like physics that are already known for multiple postdocs, etc.), making it a bad deal all around for PhD students in those fields. Overall, I think things are already allocated more or less the way you expect, and I don't think we need to piss on humanities for this. They already have it hard enough.