Tech demos are just that: demos. Very few, if any, studios will release a game on that engine with such fidelity. And given the current practice of AAA studios

Tech demos are just that: demos. Very few, if any, studios will release a game on that engine with such fidelity. And given the current practice of AAA studios now starting to charge $70 for base games and still releasing them as a broken mess, I doubt we'll see any game be as remotely exciting as the demo.