When I read that first part, I thought, yup, could have been me right here, even if that weren't your point. I think sometimes I reply online for many different reasons, typically emotional ones. I'll read something and I'll feel excited/confused/angry/annoyed/etc. about that topic or something related and will share it, often not being so aware of why I commented or how it was a mostly non-sequitur comment.

This part of human life fascinates me, where one person may assume the other posted something to show how smart they were, but the person who posted actually did so because they had an aha moment in their head and felt so excited to share it. The differing, sometimes even opposite, perspective on the person's intention.