You may be wrong.

The paper is available for download, it’s 126 pages long. I’m on page 18 49, and it’s a steamroller. Oh yeah, and Calabresi, the author of your linked article, is cited in the NY Times article above.

Edit: Just got to page 61, and there’s a bit there which addresses your concerns.

For those (like us) who value First Amendment liberties of speech, press, assembly, religion, and the right to dissent generally, might Section Three therefore be thought a little dangerous? Might Section Three, in the wrong hands or applied improperly, be used to suppress dissent in the name of excluding insurrectionists from office? Perhaps. We do not shy away from the point. But the supposed danger of a constitutional provision is not really an argument against its meaning. And the potential abuse of a constitutional power, privilege, or disqualification is not really a good legal argument against its existence. Section Three’s exclusion could be thought to pose a danger; but insurrection and rebellion are dangers too—all too real dangers, as recent events have shown. Where exactly that line is drawn by the Constitution, and the extent to which that line changes the prior rules of the First Amendment, are ultimately questions of the meaning of Section Three’s general terms triggering disqualification from future office—“insurrection,” “rebellion,” “engaged in,” “given aid or comfort to”—and of who all is included under Section Three’s ban.