This is not fully correct - while this mainly gets lost in the discusions about updating the Android emulation layer, another thing that is neglected (and a per-requisite for updating the emulation layer) is newer kernel and drivers. These alone would fix many hardware issues people are having with the Xperia X such as unusable speaker phone mode due to broken echo cancellation or sub optimal CPU scheduling.

So it's not only about the Android emulation layer getting unusable old, but also about the (related issue) of outdated drivers.