Dunno why people are using speculative language terms like may(be) or warn, when it's pretty much confirmed at this point?
When has valve ever launched a hardware product with decent availability in recent memory?
When has any vendor/OEM done so in this industry?
Let's face the facts and call it what it really is, machine/frame/controller - 2027 products. And before anyone gets excited about Helix or PS6, those too will suffer a similarly delayed fate - 2029 products.
It may not be price but availability that becomes Valve's biggest problem. In a Reddit thread, fans warn that the Steam Machine could stumble at launch if the long wait times seen with the Steam Controller are repeated.