With the wonders of forced induction, a smaller engine can create the horsepower and torque of a larger-displacement engine.
Engineering Explained goes into a bit more detail (with a lot more clarity) than that. Also, the video below briefly explains the difference between internal and external wastegates. Now that you possess this knowledge, go forth into the world and impress your automotive enthusiast friends the next time the topic of Turbos spools up.
Watch below Engineering Explained explain how wastegates work and the diferences between an internal & external wastegate.