America might have been embracing immigration more, and for longer, but the Britain you have today too is to a large extent a consequence of embracing immigration post-WWII as we needed a workforce to rebuild our country. See "windrush generation" (more recently: "windrush scandal" over how poorly some of them have been treated) . If you're living in the UK you might have heard about it on the news recently (I say with typical British understatement).

Immigration was certainly good for our economy too.