zlacker

The smoking comparison is very apt I think. People and institutions persistently pointing out that correlation isn't causation is a big part of why it took decades for the link between smoking and cancer to become commonly accepted after it was well established.

Some were surely acting in their own personal financial interests but I'm also certain that a lot of it was more nuanced and personal. People need to think of themselves as, for the most part, good people who do mostly good things. Knowingly contributing to something that makes life much worse for many people doesn't align with that and they will need to deny it. I know if you polled phillip morris employees about cancer in the late 60s after the link was confirmed you'd hear a lot about correlation and uncertainty.

HN isn't a random slice of the population. A lot of us here work in this domain or on similar products. There are certainly people in this comment section who directly worked on the core facebook product being discussed. They need to think of themselves as good still, too.

>>giraff+(OP)
Smoking to lung cancer has a very direct delivery mechanism, inhaling tar into the lungs. The effect size and sample sizes are big. The hypothesized mechanisms here - unfavorable social comparison is far more tenuous, and the sample size here is number of universities- not number of students.

These 2 are vastly different situations.

To give an example. Establishing causal effect between nicotine and lung cancer is an open question, even as the causal effect of smoking on cancer is very clear.