>>74607339NYC does have several strong regional accents though, even identifiable per-neighborhood.
but the broader point here is that the average American has what's colloquially called a TV accent which is a little difficult to describe. it's not "phonetic" pronunciation since English isn't a phonetic language in the first place, but the things that make it stand out are like... the absence of things that are used as identifiers for other accents. for instance, Americans and Canadians have rhotic terminal Rs whereas English and Australians don't. but most people just think of the rhotic R as the "correct" way of pronouncing words now (thanks to American cultural dominance) so it comes off as a bit strange to say that pronouncing the R in "war" means you have an accent