Why do we need another law to reinforce a law signed in 1986?
Because scoflaw states like New York and New Jersey are ignoring the law as it exists.
It is a similar situation to that in Florida, which had a strong preemption law, but not enforcement mechanism. Dozens of Florida cities simply ignored the law until this year, when the legislature put meaningful teeth into the law.
When city officials learned that they could be held personally responsible for failing to follow the law, and they could not use public funds for their defense, they quickly came into compliance.