

well, I mean, it’s a lack of any specific American accent. They don’t sound like they’re from the Appalachia, West/East coast, or Boston, or the south etc. etc. A lot of American television news reporters came from Columbus, Ohio back-in-the-day because we just don’t have a regional dialect.

No, I mean, the “radio announcer” and thus the “news reporter” voice was modeled after the Ohio accent, because it was seen as a non-accent. You’re right that we have one, it’s just so incredibly bland, that it comes across as not one at all.
Here’s an article that goes into further detail