Don’t know if it makes you feel any better, but this has been happening for decades.

Back in the late 80s, when I started engineering school, that’s why we joined IEEE or ASME or whatever. They had test banks, copies of solutions manuals, old homework with problems worked out, and people who had those professors who could help explain it to you. Or explain how to survive the class.

Your professors now - yeah, probably cheated their asses off back in the day but have conveniently disassociated.

There are levels of it. Copying without trying is going to bite them in the rear after a bit (usually), but using it as a guide or a check for correct work is not a bad way to learn.