It seems as though mainstream English rock has retained a lot more of the qualities of indie, progressive, experimental etc

I really wish that was the case. If we are talking about genuinely mainstream pop and rock then I don't think the British scene is any more progressive or original than any other. We just have different trends. There's loads of people milking the "soulful", sad artist thing at the moment. A lot of singers who really have nothing to be sad about trying to write piano ballads. Some of them are decent, most of them at least listenable, but they're all very predictable. There's also a lot of very cheery, slightly annoying indie pop full of extremely trite choruses and samey instrumentation.

Of course, there are loads of popular indie bands from the UK who are making excellent, inventive music and reaching a lot of people, but for every great British band managing to sell albums, there 100 more pop wannabes making dull, uninspired music and selling vastly more copies than any number of genuinely refreshing bands.

I suspect this is pretty much the case around the world, but as much as I'd like to genuinely say the UK has a great pop scene, I can't. It's as bad as anywhere else, though I doubt it's any worse.

Some great music does get into the charts, though. Royal Blood scored a number 1 album here a few months back, which was surprising, but also reassuring. I'm going to pretend for one minute that they are pushing any boundaries with their music, however what they do, they do very well and they represent pretty much the only new British rock band that's managed to really trade punches with the pop world in terms of sales for quite a while.

In all honestly, I don't think we have many bands that are popular AND good. We have plenty of both, but they rarely cross over. Personally, there's a lot of American bands that I am a big fan of at the moment. Probably more in fact than British bands.

To qualify, I'm talking in terms of relatively recent (last few years) trends, not the trends of the whole 21st century, as I was too young to be following music when the century started.

You mentioned Radiohead and Muse in your post. In terms of American bands that I think equal or surpass those groups, I would say Queens of Stone Age and The White Stripes could easily give those two bands a run for their money, and that's off the top of my head.