My parents told me of very similar setups when they were growing up in the 1960s USSR.
A roommate in the mid-2000s did similar work as a side hustle.
The actual practice is surely as old as university credentials.
That class was graded on a curve.
I got a 'B', and I would say I was in the 90th percentile for understanding the material. It would have been neigh-impossible to get an 'A' without cheating.
That's why you have to come down hard on everyone.
An academic with a cheating problem in their course has a problem they need to solve it they are knowingly screwing the honest. From a position of power.
e.g. getting a vaccine. You're arguably best off if you're part of the 1% of the population who choose not to get one but still get protected by herd immunity. But if that 1% grows to 10/20/30%, suddenly, not only does the defection advantage disappear, but the whole herd starts to suffer. Tragedy of the commons.
We're all stuck between a rock and a hard place of simultaneously not wanting to restrict individual freedom, autonomy, and privacy, but also recognizing that when being a parasite is a disproportionately advantageous role for an individual to choose, it eventually kills the host.