I have to say I had the same reaction. Sure, "prism" shows up in many contexts. But here it shows up in the context of a company and product that is already constantly in the news for its lackluster regard for other people's expectation of privacy, copyright, and generally trying to "collect it all" as it were, and that, as GP mentioned, in an international context that doesn't put these efforts in the best light.

They're of course free to choose this name. I'm just also surprised they would do so.