In my personal estimation? About two more Apple A-series generations. You can see from their focus on IPC over core count + speed (as other ARM manufacturers are) that they’re clearly tuning for desktop oriented workloads. With where the Bionic is compared to Intel’s mobile offerings, and the leaps they’re making it’s not too far off. And the only other manufacturers in their realm are Nvidia (with Denver/Denver2) and Cavium (ThunderX2).