It's not moving the goalposts, the two actions are meaningfully different. Lead is basically always dangerous, so "no lead" is an easy call and has the desired

It's not moving the goalposts, the two actions are meaningfully different. Lead is basically always dangerous, so "no lead" is an easy call and has the desired effect. The lead, specifically, was causing the entire problem, and it'll keep doing so pretty much no matter how you arrange other elements around it. Some other compounds to replace it might be dangerous, but essentially every lead compound is going to be dangerous. Carbon compounds, meanwhile, are practically endless and there's no one quality you can point to and say "that, that right there is the problem, ban that part". Piecemeal bans won't work.