People just can't live their lives looking for the next reason to be offended.I think an emotional response to just hearing about a guy you've never met sitting down on a bench during a pregame national anthem can say quite a bit about a measure of intelligence - more specifically, a lack thereof.
Now for some people perhaps this conjures emotions based on their personal past experiences, like you have described. But you also seem to acknowledge the distinction between an emotional and intellectual response. That's very absent from the majority of responses.