How would that be a false positive? The kid might not be malicious, but they absolutely are running a bot, even if unknowingly. If anything, calling attention to it could help people notice, and therefore clean up such things.
The kid isn't. But everyone else using their ISP that your ASN-based block also blocks is a false positive. An ASN block easily has a granularity of "10% of an entire large country". And nobody is going to take your site blocking e.g. all Comcast users as "oh, we should investigate which Comcast user made some slightly suspicious requests, thanks for telling us".
Fair, but we are talking about blocking just OP's site, correct? OP flagging a bot doesn't take down that ISP's access to the internet, unless I'm grossly misunderstanding the power any individual site owner has.
So is that such a bad thing? If OP is going to use this to provide data about bots, blocking mass amounts of the internet could actually be a terrific example of how many people are at least tangentially connected to bots.
