In the past, Ayaneo has been somewhat reticent to discuss its plans concerning SteamOS and as this new venture is not a direct collaboration with Valve, I should imagine that they want to test the waters first.
If this is not a collaboration with Valve, then I assume it's not SteamOS. Maybe HoloISO that is created by "fans" with the aim of installing an operating system that is extracted and rebuild from the final installation on the Deck (if I understand the project right). The goal is to have HoloISO be able to install on systems other than the Deck itself, to get a similar experience. Maybe the Ayaneo will make use of HoloISO instead?
The project still needs funding and time to be build, so nothing is set in stone. Valve also works "hard" to bring SteamOS to other systems, so maybe there is a plan to do this. Now the Deck OLED is out, Valve probably have more time to do this (SteamOS 4.0?). Either way, I am very happy and curious what will happen next.