It's not like the scores have the tiniest bit of impact on the market. So really, who cares?
Or even an impact on practical use. If the there was any real, practical value to their 'metrics' photographers serious about low ISO performance would be deserting to Sony and Nikon in their droves, yet they are not because in the vast majority of low ISO circumstances there is just no difference, despite all the crap about read noise levels, FPN etc.
I remember he-who-shall-not-be-named once posted two identical shots from a 5DII and a D800 to show, in his opinion how much better the shadows were from the Nikon, but in his blinkered vision of pulled shadows he had overlooked the noise in the blue sky from the Nikon ! When I pointed this out there was a very hasty edit
So who cares ? Well unfortunately there are a growing number of web based review sites that quote DxO, perhaps because of the way in which DxO present their data; it's seen as being very scientific. Obviously to date this has had no detrimental impact on Canon's sales, so it would seem that at the moment the majority of purchasers don't take any notice of what they are saying, but I wonder if in time it could start to impact, but I suppose by then Canon may have a sensor that scores better on DxO.