Removing tetraethyl lead was certainly doable. Removing every car from the road was not. One was a targeted change that improved the industry, while the latter was so impractical that they never considered it.
Here's a thought - you assume a priori that shutting down social media would be a net win. How did you come to that conclusion? Did you spare a thought for the people who's social lives revolve around spending time with friends online? You'd advocate for taking away these people's social networks because you're certain you know what's best for them?
