The title on the blog post page itself seems to be corrected now, but not on the user's home page.

I was looking at this too, surprised it was not fixed on the HN side yet considering how often submission titles get updated here.

Submission titles get updated if either the author (within a time limit) or a mod notices that there's an error in the title. The mods don't see everything, but do respond to email. If a title needs updating, you can contact the mods via the Contact link in the footer.