Presumably it's because ARM is a fully-baked technology that's been around for a while, with good compilers and all that, right now. RISC-V is promising, but i

Presumably it's because ARM is a fully-baked technology that's been around for a while, with good compilers and all that, right now. RISC-V is promising, but it's not there yet. A small company like Pine64 isn't necessarily going to have the resources to, for example, get the Linux kernel support for RISC-V into a production-ready state. Apple, for its part, adopted ARM years before the RISC-V project even started.