From the FDA's timeline someone posted above, they made their first consumer advisory 4 days after confirming bacterial contamination, 10 days after the first test showing possible contamination, and they pressed the company to voluntarily recall it 3 times in that 4 day period. If they'd taken action without hard evidence, in the US political environment, they might have gotten shut down entirely, they couldn't get the funding they needed as it was.

Now, if you want to argue that it should have been shut down months earlier when they found the first safety violations, I wouldn't disagree, but that would require much more aggressive laws. The way things actually work, with almost everything, is that the inspector goes out, says, "you'd better have these things fixed by the next time someone comes out here," and then leaves and doesn't come back for many months or even years. And then when they do come back if there's still a problem they can start thinking about issuing fines.