Bird-lovers have pushed an anti-lead agenda (for hunting) for decades and have been highly successful. They continue to make inroads into banning use of lead entirely:

"Bald eagles across the United States are dying from lead poisoning":

https://edition.cnn.com/2020/02/16/us/bald-eagles-dying-lead...

"CALIFORNIA'S LEAD AMMO BAN IN EFFECT JULY 1[2019]":

https://www.gohunt.com/read/news/californias-lead-ammo-ban-i...

I think most of this is anti-gun lobbying. When people are reduced to stoning wild ducks and spearing deer then anti-gunners will ask Congress to ban sticks and stones.