So first off, calling this a “deep dive” is definitely overstatement, but OTOH it is a decent primer/overview.
I don’t think Nvidia or AMD have anything to worry about in the near/medium term, but in the longer term this could be a good thing generally for a perhaps not obvious reason which is that it could/should create a more defined and stepped path for graphics performance, which should allow more flexibility and scalability for both app developers and UI design.
To oversimplify a bit, right now app designers depending on which they are coming from either face a performance cliff or no tangible benefits beyond a certain point between conventional integrated graphics and dedicated solutions.
11th gen core I with XE graphics was a major step in the right direction of course and with a small bit of revisionism is now part of the bigger roadmap.
Of course the big questions will be if Intel continues to develop it and if MS actually embraces it.
Deep Dive With Intel’s Arc Mobile Graphics: Here’s What You Need to Know | PCMag