> most human visitors will actually be unable to pass the CAPTCHA

Most human visitors will never ever notice the change. reCAPTCHA is completely invisible for most human visitors because they are allowed to pass just by fingerprint.

It's not like an average user is going to have to scan a QR code every time they visit a site via web browser. If it were like this then it would be a non-issue because no sane website would adopt this system. But it isn't.