Clearly Chuck Peddle is a major designer and engineer. So what went wrong with the new computer he’s describing?

The company filed for bankruptcy protection within a couple years. https://en.wikipedia.org/wiki/Sirius_Systems_Technology

Steamrollered by PC compatibles obviously. At the time it wasn't clear yet that for 8086/8 you needed register level hardware compatibility, not just BIOS call compatibility (as in the CP/M days) to stay in the market. And nonstandard disk format to boot.