To me it feels a little haughty. Basically, "if you think anything in this app is wrong, you are incorrect, and should go elsewhere"
Don't get me wrong, it's Marco so he has earned the right to dictate how an app is. It strikes me as more funny than anything else, but I wouldn't want people to see this and think they can replicate it without having a big name to back it up.
To be honest, that isn't a terrible approach to take with this sort of app. Sure, there'll be some problems that he'll want to fix, but it's the sort of thing where people have differing personal preferences, and you're never going to please everyone.
EDIT: Also, I think I remember him talking before about how he implemented things due to user demand on Instapaper that ultimately didn't really fit, and which he regretted. Was on a podcast, unfortunately, so no link.
Keep in mind that this is not the same thing as ignoring or disdaining criticism, it's just deciding to put it to use selectively.
No product can be, neither should it be, everything for everyone. Quite a few people thing google docs is fine, but some think it's lacking in features. They are both correct, in their own way.
Whether you choose to cater to everyone, which is a fool's errand in my opinion, is ultimately a business decision. If you think the product as you envision it will have buyers, then why not?
So the dichotomy of correct / incorrect is not as clear as you say.
You can take feedback and suggestions (and remember, feedback is in the menu above the links to other apps) but as a software developer it's unlikely your app is ever going to be all things to all people. This feels like a simple acceptance of that and a chance to recommend apps / developers he likes if what he's doing isn't for you.