They've had the program in place for years (~2012) and it is opt-in. Author didn't seem to contact Disqus to see if this was a mistake or intentional, and doesn't mention if the domain had the Revenue option enabled. He just says 'I remember once clicking an unrelated option about showing inline ads, that should have been good enough'.
https://stiobhart.net/2017-02-21-disqusting/