"Python Tutor's large international user base provides a unique platform for my research. This work has collectively led to almost a dozen research papers and several major grants so far."
In other words, he wants the (extremely large) benefits of an open source project but doesn't want to waste his time on those that don't have value to him.
He's running a startup with a $0 price tag rather than an open source project. He doesn't deserve to get any credit, it's something he does purely for his own benefit, and he's giving open source projects in general a bad reputation. Nothing that he's said is a justification for ignoring communication.