That's definitely true, but depending on the usecase it might not matter all that much. Also, that problem already applies to an anonymous blog anyway!
Consider the usage of semi-anonymous accounts on HN or Reddit or wherever. There's some risk of deanonymization depending on usage style and how determined the attacker is, but it's still quite different from openly publishing things in a manner that links back to you directly.
The issue for me is that (for an anonymous blog) once I decide to publish something to it the article becomes permanently and publicly linked to all the others as well. This means that I can never change my mind in the future without simultaneously changing my mind about all the other content published there. It also means that if I ever slip up (say on a non-anonymous HN account) and reveal that I'm the author then I've inadvertently and publicly tied the entire blog to myself (not just that one article).