A liberal arts or pure science education is not meant to be a professional degree. It's a way to learn a lot about a particular topic, independently of whether that directly helps your employment chances or not.
Historically, there was a fairly sharp delineation between universities and vocational schools--even "white collar" vocational schools like engineering were at separate institutions (often A&T or A&M schools), and lawyers and doctors were primarily apprenticed. At some point doctors, and later lawyers, became highly skilled professions that needed more formal training. To a degree it made sense to combine medical schools with pure sciences under one university, since some of the basics overlap.
But it had the unfortunate side effect of starting the thought in people's minds that universities are vocational institutions, rather than institutions of higher learning. I certainly don't mean to insinuate that a liberal arts degree has no application in the real world--quite the contrary. But it's intentionally targeted at longer-term learning rather than particular vocations per se, and not everyone who pursues a higher degree does so as a job entree.
Nonetheless, the law schools and med schools were followed by a spate of mergers between technical institutes and universities. Suddenly non-university vocational institutes were looked on as crappy and inferior, and it became a mantra (for no good reason) that you needed a 4-year college/university degree to succeed at jobs that historically had been done quite successfully without it. Even a shorter professional program started to become more prestigious if allied with a 4-year college, for no good reason (e.g. nursing schools at universities being, generally, valued more highly than independent nursing colleges).
The result was a massive spike in the number of people going to 4-year colleges--that number has sextupled or so over the past 60ish years--and a massive decline in the number of people going to vocational and technical schools. The latter have become a joke to the point where vocational school brings to mind TV commercials for Devry or Andover tractor trailer driving or dental hygeniest schools.
The downfalls of this are manifold. University prices skyrocket as everyone seeks to get in, whether they are really interested in a university degree or not. Vocational schools fold and a large percentage of the people who'd have attended them are forced into universities, exacerbating #1. Jobs see more and more college degrees, and start expecting them, making people start viewing colleges and universities as professional/career prep schools.
And universities become disincentivized to teach pure liberal arts or even theoretical mathematics, as they start being judged based on how good they are as job factories rather than as educational institutions; the result is a short-term focus that harms long-term research and eventually job opportunities (much akin to eliminating R&D budgets, but on a national scale).