I think that's because 23 And Me's tests actually did what they said they did. The problem with 23 And Me was that all about the reporting of the results, not that the results were fundamentally flawed. The FDA's problem with 23 And Me was that they were coming very close to, and perhaps were, crossing the line into giving medical advice. It's legitimately very hard to interpret the results of say a BRCA1[0] test, and so doing at home isn't recommended.

In the case of Theranos, there are high school biology labs that are run safer and better.

[0] http://www.cancer.gov/about-cancer/causes-prevention/genetic...