Twitch unleashes scorched-earth attack to unveil malicious spambot creator

It is interesting to see the 'official' approach to doxing in relation to the unofficial version (calling them out on places like 4chan). Krebs does a lot of this sort of sleuth work and given the obvious market for people who feel harmed I'm wondering if there is the internet equivalent of a private deteective. People who most closely meet that criteria that I know are generally on retainer to lawyers it seems.

I don't understand why twitch can't easily nip this in the bud? I assume to comment you have to be a logged in user. Simply throttle comments per account and put tighter throttling on newer accounts. Am I missing something?