Full Fact provides an unbiased, unabridged analysis on the safety of eating chickens rinsed in chlorine. It reports that the EU’s food standards arm says there are “no safety concerns” with the process of washing chicken with chlorine, but has raised other concerns about hygiene.
Whether you accept the US or the European viewpoint depends upon your perspective. Both have validity. But I think that the European view is more natural. There’s a long history of scientific evidence in the US being reversed. Just because using chlorine is regarded as safe by today’s scientists does not preclude future evidence to the contrary.
Perhaps, for US consumers, convenience and low-cost ‘trumps’ hygiene and taste?