As for the Unix Way (tm) I think the folks at PARC were honestly puzzled, if they thought about it at all. Most were Tenex sorts of folks, or interested in languages, GUIs, and distributed computing. Unix was time sharing, and something you did if you didn't have your own computer.

I was at PARC in 1984, working with Dan Ingalls. I mentioned I was surprised that Smalltalk had no concurrency†, that the UI (let alone the system) was completely single-threaded. Only the window with focus could execute any code. Dan being Dan, he immediately got to work making a form of concurrency happen, followed by a delightful orgy of researches playing with the new toy. I loved it.

Because: sometimes in isolation you miss important things going on in the outside world.

-rob

† The starting idea for the Blit né Jerq‡ was bringing a UI to Unix that supported parallel execution, after a demo of the Three Rivers Perqs at Lucasfilm, an emulation of the Alto, and seeing only missed opportunities.

‡ The name "Jerq" was Lucasfilm's own moniker for the Perq, and we asked them for permission to use it, which they happily provided.