Are you sure about that? In the US, I’ve read anecdotal reports about people with Southern accents facing discrimination.
In Canada, the Maritime provinces have a distinct accent and there has been a culture of joking about “newfies”[0] (perhaps that has subsided recently).
Are there laws that apply to these situations? Laws can also exist on paper but almost never see enforcement.
https://www.cdpdj.qc.ca/en/your-obligations/prohibited-groun...
Any human rights tribunal in Canada would agree. The law in every province is the same. It goes the same way in a lot of places beyond Canada. A person cannot fully control their accent, and the way they speak is closely tied to their ethnicity, background, nationality, disability, etc., and stigma and prejudice about accent is not permissible. If the employee can communicate effectively, then discrimination on the basis of them sounding slightly weird, is illegal.
Whether the law corresponds with reality is a different question. Such discrimination is widespread in practice and hard to enforce.