He’s been denied accreditation for his business to resell certain domains, not kicked off the internet.
Would it not be reasonable for, e.g. a publicly owned national electricity grid to refuse to accredit a new energy business which is run by someone who previously published “how to circumvent your electricity meter”? I don’t even know if such a thing would be illegal to publish, but even if it isn’t illegal, I don’t think it’s unreasonable for accreditation to be refused.
It would not just be unreasonable, for a rehabbed offender, but also stupid. The people who know the ins and outs of systems are the ones best placed to suggest improvements to the status quo. I wouldn't think this necessary to be explained on Hacker News, but here we are.