assuming someone ever gets round to working out how to deliver it without compressing it so fiercely that it's pointless anyway.
I think this is partly the point. Look at how Sky SD went completely down the shitter with even more chronic compression once Sky realised they could charge more for a rather substandard HD attempt. Sky HD looks so much better than their SD service, but this is only really due to the artificially poor SD they provide.
This is why Freeview is so much clearer than Sky SD.
I believe the only UHD broadcasts in the UK are BT Sport? I know a little bit about it, and because of the nature of how it is moved around, and then broadcast (each quarter of the picture is a separate 1080p stream), the compression has to be the same on all 4 streams (ie, light), as any latency differences will cause a quarter of the screen to go out of sync. That's not to say as encoders and technology improves that compression can't increase...