DAB in the UK offers much better variety than regular analogue radio (FM or MW) in a user-friendly system that provides superior audio. Plus, the market penetration of DAB on that side of the pond is very high so most consumers have access. I brought a little Roberts portable over there and was blown away by how great the system is. In a big city, like London, there are so many stations available that you are sure to have several favorites. But where it really shined was in a place like Stoke-on-Trent, where there are probably only 5 or 6 FMs with good signals, but more than two dozen channels available loud and clear via digital.Anyone who is wondering if switching off AM reduces ratings - Absolute Radio recorded its highest ever cume and one of its highest shares in the most recent quarter, now that it is a DAB and online only station.
Anyhow, the point of that last paragraph is that Absolute Radio is heavily invested in DAB and offers multiple channels across the UK (though not all channels are available everywhere but the main ones are).
With that kind of platform, in addition to streaming - the AM/MW signal was truly an afterthought and probably didn't bring many additional listeners. 99% of anywhere the MW signal goes in the UK, there's a digital multiplex offering a feed of it in crisp stereo and with a superior signal. As for the other 1%, they probably won't lose one pence without them. It's mostly a negative for dxers like us to have this transmitter turned off - though many other MW offerings are still available in the UK.