I mean even HN employs that pattern (though not necessarily intentionally). Whenever you refresh the page you have a random reward in the form of gain/loss of karma or comment replies.
Should we ban HN?
Should we ban HN?
[0] except the YC jobs ads
I think intent matters for a lot here, as does who/what is pulling the levers. If popular content organically rises to the top because people like it that's not really a problem, but if content is artificially pushed to the top or hidden entirely to push an agenda that could be an issue.