Courts are finally punishing Big Tech for harming kids. Here’s the catch.

This week, juries in California and New Mexico dealt a pair of landmark verdicts against America’s social media giants. 

In Los Angeles, jurors awarded $6 million to a young woman who alleged that Instagram and YouTube had damaged her mental health. A day earlier, a jury in Santa Fe ruled that Meta had designed its social media platforms in a manner that harmed minors — and ordered the company to pay $375 million in recompense.

These decisions constituted a breakthrough for a legal...