For the probably young students their biggest concern is having to be isolated for 2 weeks away from their friends and studies. The isolation is probably a bigger risk to their health than the disease.
It's the older staff and surrounding community where the health risks are much higher that these infographics deceive.
It’s not only at MIT, all the world reports infections like this.
In the number of daily cases we don’t know how many are new cases and how many are already in quarantine
But for countries you can get the total number of people currently with the virus. What the article says is that universities only report their positivity rate.