Also with respect, it seems to me that OP posted here in order to find support for his naivety. He hasn't found what he wanted, and hasn't learned the lesson yet.
Actually, the OP posted here to get advice about what to do in a situation where an AA staff member pursued him off the plane and more or less indicated that AA would be conducting an investigation. It's the respondents here who have instead turned it into a morality play concerning the wisdom of, and motive for, the actions that led to that situation.
It's FT, of course, so everyone feels entitled to pass judgment - I get it. But given that we're now 35+ posts in, the ongoing scoldings and soapbox speeches have become repetitive, and dare I say tiresome. 🙄 I see no indication that the OP is planning to offer his seat to a minor, or probably anyone else, again in the future.