What a strange rant. First of all, this guy continued answering and asking questions since he published this article, so I guess he changed his mind about deleting his account. http://stackoverflow.com/users/2189331/jdevlin Secondly the italic bits about how he should be allowed to delete questions because he created the content make no sense. All SO questions and answers are collaboratively created so he can't claim…
You can always get to older content even deleted content through the regular Creative Commons data dumps that the whole Stack network publishes torrents of. You can also, if you sign an NDA, get a more complete data set for research purposes.