The problem there is that FDA has statutory authority to regulate some things and not others. (The notorious exemption is "natural supplements.") But the FDA takes a remarkably thorough approach to what it does regulate. Let me give two examples.

Example one: I have been in two FDA-regulated medical trials. One was a placebo-controlled trial of taking fexofenadine daily for indoor allergies. I had no idea if my numbered supply of tablets was placebo tablets or genuine tablets. I had a schedule for taking them, and had to keep a detailed log of symptoms. The second clinical trial I did was a trial of consumer-facing store displays for a proposed over-the-counter medicine for controlling cholesterol. At the test center, there was a mock store display that looked just like the shelves of a pharmacy, and I read the mock labeling and then was asked several questions about my understanding of the purpose and use of the drug. I was even given a brief IQ test as part of the trial, to see how my understanding of the store display would compare with that of someone with a different level of IQ. The FDA is thorough, and it relentlessly uses carefully gathered data and statistics analyzing those data to make regulatory decisions.

Example two: My son the hacker had a summer job while still a university student writing code to control the display of a test device to be used by medical doctors in a hospital or clinic setting. He had to think through all the user interactions medical doctors would have with the device, and how to code the device so that it would have high usability for doctors and high reliability. As he neared the end of his summer job, medical doctors came to the medical device company where he worked to do carefully monitored usability testing of the product. My son told me at the end of the summer that the product he worked on would have to be tested with regard to all aspects of hardware and software for several more years, including a complete line-by-line code review of all his code by FDA specialists in software. He heard from his bosses that time to market for that product would be as much as five years after the summer when he worked on it (in other words, still in the future today). The FDA is very thorough in its regulation of medical devices. I also know this from an electrical engineer who is a childhood friend of mine, who has long worked in another medical device company in our town, which has major medical device companies headquartered here. Safety is job one at the FDA. Effectiveness is job two. Both have to be proven before a new drug or medical device goes to market.

Simply put, the people at 23andMe have been doing what a mathematician calls "hand-waving," concluding things that they haven't proven. That helps develop a kind of zeal for the task for the long haul, but it doesn't ensure that the task gets done right.

i should make clear, i absolutely think 23andMe are in the wrong. very very far into the wrong.

the fact that the FDA are effectively impotent in many areas they are not is largely irrelevant, but I enjoyed seeing it brought up since it is very true and also a real world problem with a measurable impact on the economy and quality of life.