Correct.
I don’t see how you can say this won’t be helpful when it takes a week to schedule a test or takes hours of waiting to actually get tested. I don’t live in a densely populated area either. I’ve seen some insane excrement in the NY area.
If we’re saying they should have done this much sooner, yes, I agree. Been saying that.
It also has nothing to do with the UK, other countries are doing this too.
I've already explained why it won't be helpful, or rather why it has proven to be a net downside. There are lots of other reasons as well, such as the massive unreliability of these tests leading to inadvertently counterproductive behaviours e.g. symptomatic people testing negative and deciding that means they can get on with their lives despite the very high chance of that negative test result being incorrect, and the excuse it provides for not scaling up and providing worthwhile public testing infrastructure.
It's very typically American though to say "I don't care what the result has been elsewhere because we're so very different".