The 300 mg dosing was adults, and they specifically said above it hadn’t been tested in persons under 18. Little kids metabolize things differently. And most of the overdoses are gummies, so we’re talking about coming in and potentially finding your greedy little goober has eaten your entire jar of 60 CVS gummies at 10 mg apiece. Trying to get them to puke while they’re so sleepy could cause aspiration, and they’re going to need monitoring to be sure they don’t stop breathing, so it’s off to the ER. And with the observation of widespread inaccurate dosing/labeling, the amount and type of drug ingested can only be guessed at.
Requiring a child guard cap and warning that effects in children have not been studied doesn’t seem unreasonable. And quality control tests to ensure you’re getting what you expect.