Recently, an option seems to be ignoring authenticity completely and have actors perform in their native intonation. The hope is that the focus on the accent will fade away and cause viewers to stop caring about it.

The focus is more about being authentic to the essence of the story, rather than every tiny detail.

Speech systems, rather than accents or dialects, should take into consideration the diversity of human speech and acknowledge how voices are informed by age, gender, time and cultural context.

A speech system without a full exploring of the context will come over as fake.

How we judge accents often comes down to how important we think authenticity is.

Authenticity is probably not an essential element in a story. What we believe about a story is more important than what country or region a character sounds like they're from.