I suspect the reason why ANC is not in every bud is that it may...

I suspect the reason why ANC is not in every bud is that it may be extremely difficult to incorporate in a true wireless, low power and discreet form factor. Look at earbuds like the Samsung Level-In or B&O's E4, both wired but using the same / similar AMS chipset to that specified for the LiveIQ (AS3412 / AS3415). The ANC componentry does not sit in-ear but needs a seperate box unit on the in-line cord.
The one true wireless earbud with 'in ear' noise cancelling I can think of is the Sony WF-SP700N, not what I would call the sleekest design.