[marcosdumay]

I think the article's author didn't even think about separated onboarding and confirmation emails. He's just stating that you can use the confirmation one for onboarding too.

I have seen those separated emails. I agree that they add nothing, and I imagine their conversion is much lower than a single email (they don't bother me, I'll just ignore another message). I do agree that onboarding is best done on-channel, but adding an extra link on the email you are sending anyway can only help.