But it has few available chips right now, none of which are ultra-pow-power IoT app cores, and the big stacks like Zephyr & Matter & NuttX & FreeRTOS only support a sprinkling of chips anyways.

I don't disagree with you per se, but it's still such early formative years & progress is slow.

The core is just such a small part too. It's great to see risc-vites starting to spec our the rest of the platform too. But like the first decades of ARM, it feels like most chips especially lightweight ones have bespoke Device-Tree configuration, rather than real platform.