That is what they are doing. In fact, the article (or Wikipedia), says India has already made it illegal/discouraged to go near the island.
1. These tribes have not developed medical immunity against the kind of diseases we're host to.
2. They're truly wild and curious like us too. Protecting the former quality needs a restraint from our side.
I've been to Andaman & Nicobar in 2004 and did feel a sense of excitement and curiosity when at the edge of our side of world. Check out this fifteen year old video on these tribesmen, their walking manners and the gap that we're talking about here [1].
Andamans have a tremendous diversity with its colonial history, modern day torture equipment at Cellular jail that the Brits used during their rule of the region, and exotic tribes like these. Apart from blue beaches and coral life that most tourists love to see.
We really do need to fight the urge to put nike's on them, although I must admit to being interested the number of things we might learn about ourselves from studying these people. But then again, I understand the Schrodinger's "People" analogy.
North andaman (Jarwa) tribes at the time were hostile, which I believe since the construction of the Andaman grand trunk road have become more subdued.
Compared to Jarwa, the sentilese have it better, they dont share their island.