Increasingly the arts are being defunded based on a similar argument, and humanity as a whole is worse off because of it.
If you are getting education because you are interested in the topic but won't get a job in it: I fully support this. However you should not take a loan out to get this education: there are too many other things to do in life that you also will want to do. Worse the loan means you cannot change your mind later if you are wrong (or you can, but you will still have to pay for the mistake instead of whatever you are interested in today).
There is one other reason for education: to become a better citizen (don't fall for bad politics). However that should be to everybody and I haven't seen much evidence that higher education really helps much.
In some countries they do, in some they don't, in others every PhD student even gets a scholarship. Every person I know who did the PhD did it because they loved the topics they were studying. The author of the blogpost is from Russia, I bet he didn't have to pay for his PhD.
If a PhD cost $0, it still costs a craptonne of time.
All the smartest people I know left school when they were 15 (or earlier).
Something could be valuable despite being "useless" but not in this case.