Maintaining hardware compatibility with any PC hardware ever created is indeed nigh-impossible, so you'll note I didn't even mention that. I only talked about m

Maintaining hardware compatibility with any PC hardware ever created is indeed nigh-impossible, so you'll note I didn't even mention that. I only talked about maintaining compatibility with applications written for their own operating system. Something that Microsoft does have pretty much universal control over. The only mention I made about devices was regarding the printer driver issue with Vista, which had nothing to do with the devices and everything to do with Microsoft totally redoing their printer driver implementation on the OS level. It necessitated all drivers be redone and some manufacturers (like HP) took the not very admirable path of telling customers they were up a creek.