They do, but that's really not necessary. In the linked video you can see Windows 8.1 is pretty well optimized compared to the other Windows versions. A lot of

They do, but that's really not necessary. In the linked video you can see Windows 8.1 is pretty well optimized compared to the other Windows versions. A lot of this slowdown is just developers getting complacent and getting used to the new hardware capabilities. Windows has a lot of low hanging optimization fruit laying around. It's just Microsoft doesn't really care about that: it doesn't fit the business model at all.