I would comment to say that I rarely bother to sign up to websites just to post a comment to an article, but I'd need to sign up to do so. (Wee, positive feedback loop!)

Much of the comments are tl;dr material, too -- and many of the ones that I did read were just regurgitating the same old crap ("enforced registration keeps griefers out": yet I need more than one hand to count the number of forums I've left because of fully registered, well recognised and clearly identifiable griefers).

I'll generally sign up where there is some sort of service I'm interested in; but reading and replying to discussion do not, in my book, count as services. If what I want to say stands on its own without an identity attached to it, then I don't see why I shouldn't be able to post it anonymously -- and if it doesn't, it's hardly worth bothering to register for.