That is a straw man argument, but I'll indulge again.

No amount of lead is safe, and a random sampling of newly built houses testing water from the cold kitchen tap as well as hot and cold from the bathrooms found lead above the current regulatory limit, and 5 times higher than the proposed new regulatory limit.

https://leappalliance.org.uk/litw-blog-15/

https://www.ifeh.org/docs/scientificreports/scottish_new_homes_lead_survey_%20summary.pdf

One study has shown a clear response in infants where blood lead levels increased by 1µg/dL with drinking water that exceeded 5 µg/L. This is already worrying since it is now believed that blood lead levels as low as 1-2µg/dL result in negative health effects associated with fertility, neurological, cardiovascular, and renal disorders.

https://thewaterprofessor.com/blogs/articles/drinking-water-lead-and-iq