I think most British people who say they can do an American accent are so bad at it. I find it excruciating. I find it excruciating the other way around, too. ↗
The accent got lost somewhere along the way. I'm a little embarrassed about it. When I arrived in LA I assumed I'd be able to put on the American accent. It proved difficult so I had six months working with a dialect coach and it's become a habit. ↗