Wow what a false generalisation. As an academic across communication design and IT (i.e. humanities v science) I will say you are wrong. I have seen disengaged students across both major areas. It's not discipline specific and it not just the quality of degrees. Consider the readiness of students.
I completed a year long TAFE (TAFE is technical school, 5 days a week) like foundation course prior to studying communication design at university because I originally began a degree I quit after two weeks and it was too late to restart another degree. Myself (and other students) that competed this foundation year had a major advantage. We already learned the basic tools we would need and practiced concept development so university for us was a better space for us to learn an experiment. Considering teaching contact hours a year in a TAFE is like two in a uni. Guess what! This foundation course which ran for more than 20 years lost its public funding. Furthermore, the degree I had to apply a portfolio to enter now takes in much more students with no portfolio and more or less similar amount of full-time staff with casuals picking up the rest.
The problem is multi-faceted. The honest truth is any coalition government (this is the Aus Liberal Party for U.S. folk reading) is ideologically hell bent on removing public support of anything they can. On top of that they load other ideologies about the humanities being less important than the sciences. I'd start by not commodifying tertiary education and giving students the opportunity to explore and discover their flair with smaller and richer courses before going to uni.