QR should look MORE like QR, and always include an URL next to it.
If you display a QR Code with some url, and fail to show a shortened url next to it for people to type instead of scanning, you either fail basic common sense tests, or are intentionally being an asshat.
... or the QR code isn't meant exclusively for direct human consumption?
A QR code is quite information-dense. With even the highest error-correction rates, a 53x53 QR code will store 100 bytes of information (https://www.qrcode.com/en/about/version.html). That's more than you can replicate in a URL intended for typing.
For the case of the 'Show HN' here, think of semi-automatic uses of the QR code that still use the provided aesthetic potential, such as inventory-control stickers that look like the owning organization's logo.
If you display a QR Code with some url, and fail to show a shortened url next to it for people to type instead of scanning, you either fail basic common sense tests, or are intentionally being an asshat.