There is an accent that is typically called "standard American" or something along those lines, which is what you'll hear on things like national news programs. I'm not sure how many Americans actually speak with this accent, but it's usually the one that all of these devices target initially.

Yeah, I was thinking along the lines of "General American"/"California English":

- General American https://www.babbel.com/en/magazine/united-states-of-accents-...

- California English https://www.babbel.com/en/magazine/the-united-states-of-acce...

The "Standard American" accent is the west coast (mostly California) accent. It is far from universal.

It is Midwestern and, while not universal, it is the majority of speakers on the coasts and people I have met from the Midwest.

It's essentially how a homogenized middle+ class of people born/raised in/around metropolitan areas that aren't in the South/Texas speak. (In general, stereotypical accents associated with various cities are mostly more of a working class thing, e.g. Southie in Boston.) The South is the main outlier. Colleagues I work with from and living in North Carolina generally have a distinct southern accent albeit a mostly slight one. But, yeah, historically we'd have called it Midwestern.

I think historically we'd probably have said it was Midwestern. But, yeah, however the network news anchors speak.