I disagree, Premji's "reluctance" to wear his religion on his sleeve is more to do with his ability to keep religion where it belongs, in private.
One need not flaunt religion, religion is a very personal choice. Forcing other people to behave the way one thinks is right is against humanity. As somebody here mentioned, Mr. Kalam doesnt remind Indians that first he is a Muslim, he is looked upon as a role model, but it does not make him any less a Muslim. Like wise, people with celebrity status in India dont flaunt their religions, be it Viswanathan Anand, Sachin Tendulkar, Bishen Singh Bedi, Ratan Tata, Mohammed Azharudding, Kaif, AR Rahman, Remo Fernandez, John Abraham, the list can go on. Its all about understanding to keep personal things personal.