There is a cult mentality and the cult members are happy with what they got, even if it's not exactly as advertised however it's not just about the cult mentality but it's about the overall experience of the product.
I think if Elizabeth Holmes delivered slick blood testing machines that work no different than those on the market(large amount if blood instead of a drop), but had better workflow and user experience, Theranos could have been a success like Tesla.
She tried to imitate Steve Jobs, had she imitated Elon Musk she would have been fine. She should have had the Siemens machines modified to work with modern GUI, developed some automation for drawing large quantities of blood in a pod at the mall and integrate all that with the healthcare and keep repeating that in 2 years just a drop of blood would ne enough.
The only difference between Musk and Holmes was that Musk actually delivered something that had some redeeming properties.