There is no hard data, of course. But a quick look at Kodi communities, for instance “Addons4Kodi” on Reddit shows that the vast majority of the top posts are dedicated to piracy. And even dipping your toe into Kodi communities shows it pretty clearly.

> Isn't that to be expected of literally any media player software?

I guess how you define the term. Apple TV? No, I’d say the majority of users are watching copyrighted DRM streams. But it’s definitely media player software.