Even if it was feasible for AMD to have a RR 2c/4t desktop APU available, how many of us would actually buy it? Given that folks, including us, are keeping computers longer it makes more sense to spend an extra $30 to $40 upfront due to this.
Dual cores are perfectly viable for mobile market (even for gaming), NUCs and similar media consumption devices, even for low cost enterprise mobile and desktop. It could also work for lowest end gaming for emerging gaming markets in third world countries, and internet caffees. If AMD has production capacity- I want them to make 'Banded Kestrel' as soon as possible for all those previously mentioned devices- even when established desktop gaming market is mostly past dual-core.
Selling something doesn't mean you are making a profit. They can still offer Bristol ridge in sub $100 space. A 2-core raven ridge would either mean disabling most of the hardware in current die or make a new one. The later is of the table because it's against the modular design of Zen that comes in 4-core blocks. There won't be a 2-core design.
CCX'es work just fine with some cores disabled in them- that already proves dual-core CCX can be made.