The article says they are using the tests as a threshold. It sounds like they don't care by how much you pass the threshold, just that you have passed it.
I'd expect that most students who will be able to survive at MIT can make the SAT threshold with no gaming of the test and no test prep other than maybe doing one or two free sample tests.
Someone who could not easily make the threshold on their own who games their way in is just going to find that the coursework crushes them. All that gaming their way in gains them is the ability to in a year or two add "flunked out of MIT" to their bio.
Eh, not so sure. The "threshold", if we really trust that they do threshold and don't consider overperformance beyond that threshold (something I am skeptical of), is likely quite high.