I think the question is whether Cyberpunk 2077 would ever have been made under the constraints that Blow and Muratori talk about. Like, Order of the Sinking Star looks pretty impressive, but from what I can tell it's basically just a bunch of Sokoban-style games operating on a fixed grid. You don't need anywhere near as complex an engine for that as you do for a game like Cyberpunk 2077.
My impression is that the Blow/Muratori style works well if you're the only person working on a game, or part of a very limited team, which is fair enough, but it naturally limits the scope of what you can achieve.
The Witness is a 3d engine made from scratch. Not all AAA companies use Unreal or Unity.