Oh good lord not that statistic again.
Left unstated is what jobs philosophy and art history majors take.
There's more computer scientists working in computer science than there are philosophy or art history majors working in philosophy or art history.
Philosophy and history majors are for people who have no idea what they want to do. So a decent job in any field is as good as any other.
CS majors are working towards employment in a specific sector, and aren't likely to accept anything else very readily.
The article mentions this. Unsurprisingly, the CS grads are more likely to get jobs that require a degree.