For example, a detail in this conversation. You keep bringing up how 10 is "just so young". It's almost like you're more interested in the youth aspect than the other stuff. From my perspective the detail about age is the least interesting part of the experience. But maybe you are trying to get at or share something of your own that I am not understanding.
In hindsight I could have just called BS on your comment. But when the content of the BS happens to exactly intersect with painful memories from the past (which I specifically alluded to in earlier comment about social isolation, insecurity, etc), and when you don't reply when I ask you to share more about your intentions or background — that's a red flag for my finely tuned troll detector.
Pro tip: if you want to ask deeply personal questions without looking like a troll, all you need to do is give context by sharing a bit with vulnerability from your own experience.