[buescher]

Somebody's buying enough licenses to keep them in business. You either find a computer algebra system useful for what you do or you don't. My needs are pretty simple and Wolfram Alpha works well for me when I need something like that. Better than GNU Maxima, which I also like.

Stephen Wolfram made his early reputation in part by being one of the first people to seriously use Macsyma for physics. No, I don't know any physicists that take A New Kind of Science that seriously, but that's a different story.

Jupyter is hot, but it's not novel. The Mathematica notebook interface was an innovation and is still best-in-class in my opinion.