My guess is the little cores are mainly for OS background jobs and a view applications which explicitly opt. for it.
Also while they have different instructions sets they don't have a different arch, i.e. they have a "shared base" of instructions which likely are good enough for many background applications. Like updaters, downloaders, background mail fetching programs etc.
In the end it fits in with their "always connected" approach. Through I'm still somewhat skeptical about the "always connected" approach. Like even in many first world countries always connected is just not a think for many users. Even on phones it not fully given through much more then on laptops.
Also while they have different instructions sets they don't have a different arch, i.e. they have a "shared base" of instructions which likely are good enough for many background applications. Like updaters, downloaders, background mail fetching programs etc.
In the end it fits in with their "always connected" approach. Through I'm still somewhat skeptical about the "always connected" approach. Like even in many first world countries always connected is just not a think for many users. Even on phones it not fully given through much more then on laptops.