It is outrageous to say an early stage company giving inaccurate diagnostics "is like" giving patients incompatible blood transfusions.
10-15% of people who get the wrong blood die. People who get inaccurate diagnostics get scared.
Very different and this undermines the credibility of your otherwise valid point.
That's only true if those people always follow up with a second test using traditional means. If they don't follow-up and instead immediately go past diagnostics into some sort of action, then it could be catastrophic in a manner exceeding being scared.
Now you can argue that if the patient is working with any medical practitioner worth their salt, that med will surely ask for a second test. But is it obvious that that will always be the case?