Well, no, the courses at a community college may not be directly comparable/equivalent to the courses at Cornell. But one could say the same thing about high school preparation - not all high schools are equal, and I’m sure that the education at Stuyvesant or Andover gives better prep to students than the education at the local public high school in Compton or Newark.
However, those students from Compton or Newark - or the local community college - may have other traits and capabilities that the Stuy kids never had to develop. If you come from the poorest high school or a community college and catch up to your classmates at Elite U, that shows some ambition and perseverance and a strong ability for self-directed learning.
The question is really not whether these groups of students are distinguishable from each other, but whether the differences are large enough to make some kind of difference in their performance on the job or in graduate programs. So far it appears that employees and graduate programs have decided it does not, since they hardly seem to care.