Sadly, there are more people with that kind of deep calling and sense of duty to the next generation willing to put it above a better salary than universities need, so as long as that will hold true, universities will be able to get that highly educated labor for very cheap.
I have several friends who are adjuncts making barely more than I used to make as a grad student, and who are living in borderline poverty (fortunately for now they are young and dependent-free, so it's not too much a sacrifice). I can very much relate to them, as I miss teaching terribly - but I refuse to give cheap labor to what many US universities have become, ie investment firms with an education themed PR front (https://www.nytimes.com/2017/09/19/business/dealbook/harvard...).