I've noticed that, regardless of where one resides in the US, the local TV News personalities, all speak with the same vanilla, midwest accent my ears became familiar with growing up in Michigan. There are west coast accents, east coast accents, southern accents, accents in the the far north, (Places in Minnesota & the upper peninsula of Michigan resemble Canadian/English accents.....as do many 1st nations people's) but the local news personalities, regardless of region, all speak with a very flavorless accent. This may be partly responsible for reinforcing stereotypes too. This is a fascinating topic. Accents that evolved from those didn't learn English as their first language, my are favorite!!!!
Thanks for sharing your perspective. ✌️