Let’s assume it costs a few million to design this chip, well you can already buy a an i7 which has 4 cores runs at 3.06GHz costs about 250$ in bulk. That’s 4,000 CPU’s per million in development costs before they see a single CPU off the line. If they get something 20% better then they are looking at a few hundred thousand chips to break even.
PS: They suggest that it’s going to be 30% slower than a 6 core chip which suggests it’s on par with a current generation chip 4core CPU.