i think PhD programs and advisors did make some implicit or explicit promises to recruit students to work for them, very hard, for years, at very low salaries.

the PhD is not like a master's program, it's an apprenticeship relationship where you essentially work for a senior professor, and your work directly financially benefits the department as well.

so there is a deal here, but if one end of it is collapsing, the students in some departments might very well feel betrayed -- not by society but by their advisors and programs.