Oh, sure! But the primary purpose of regulatory enforcement is to catch people lying, and Holmes was pretty effective at exploiting the weak points in the regulatory regime to avoid that detection.

What? Holmes (allegedly) misled people that were willing accomplices in being misled. There wasn't a regulatory failure, just investors that did not do their homework.

So beyond the investors, Theranos injured quite a lot of real people. They were actually doing blood tests, which largely did not work. With different regulation, some of this might have been averted (in particular, if the FDA was responsible for diagnostic labs, that might have helped).

Frankly, dodgy companies screw over the people unwise enough to invest in them every day. Theranos was unusual in that it also directly screwed over members of the public.