There are two issues to consider here: whether he is correctly identifying the people he doxxes and the ethical implications of his decision to do so. He received a fair bit of backfire for doxxing security researchers a few years ago (including @notdan) https://itwire.com/security/infosec-researchers-slam-ex-wapo...
For me (and I'd imagine most folks coming to a board called "Hacker News"), doxxing independent security researchers for the crime of port scanning is highly unethical behavior, and this vigilante crusade to doxx hackers is appearing to generate yet more collateral damage in the reckless pursuit of clout.
I suppose we can never truly know what motivates anyone to do anything. I'm not committed to that stance, but even if he had the most pure of motivations it wouldn't materially change the consequences (both ethical and practical) of his actions.
For me (and I'd imagine most folks coming to a board called "Hacker News"), doxxing independent security researchers for the crime of port scanning is highly unethical behavior, and this vigilante crusade to doxx hackers is appearing to generate yet more collateral damage in the reckless pursuit of clout.