Thanks, a fascinating read. I came across the term relatively recently too, and wrote a slightly overwrought reaction to it that was more knee-jerk than considered - https://medium.com/@adoptionthoughts/the-fog-18f63ce6d140 - due to the way I found out about it.
I realise this is really about a conversation between adopted people, and perhaps stems from those systems that don't support or enable adopted people to learn about and understand the decisions adults made on their behalf when they were young children. But we all need to realise that the Internet is a global phenomenen and that we'll not all share the same experiences, the same culture, the same morals or the same ethical responses to what can be an incredibly complex individual situation. Adoption is a word with many meanings. When thinking in those terms those people bandying about insults unthinkingly, just because their targets don't agree with their own personal (and very limited) worldview seems a bit selfish and presumptive. They need to bear in mind that children and vulnerable people will read their posts, no matter what the minimum age rating a particular app is supposed to have. The phrase 'fog' seems to cause more 'Fear, Obligation and Guilt' than it prevents.