It's not doing a memory check, that takes ages and I turned it off.
But it is quite true that BIOSes are so opaque (and so badly written) that it could very well be spending its time doing something else, probably terribly inefficiently!
But, still, the 'need to write everything' and the ever reducing ratio of memory bandwidth to RAM volume *is* eventually going to have the effects I suggest above, even if it isn't now. So it's good that Linux already has the machinery necessary to fix it, if the BIOSes would please catch up. (Actually, looking at the article more closely it had this from 3.2 or thereabouts, since all this needs is plugging, not unplugging.)