Kodi is also a general purpose media player in the first place. There are enough websites on the Internet that would conveniently offer you such content to click and stream (no need for torrent, unpack etc.)
In general Kodi does the same thing - it streams that content over your device (again no torrent, unpacking etc.)
At the end the only real difference is the advertising of that box - meaning if I would somewhat distribute a firefox browser with the proper links and call it the watch any media for free browser I would be in trouble.
Yup and that is why selling a generic Kodi box is fine. Loads of places sell them without issue.
The issue here is that these five people have taken a normal Kodi box, modified it and then marketed it as a device designed to violate copyright.
The real issue here is how these people were advertising and selling the device. It raises interesting questions though - would they get into the same amount of trouble if they sold a generic Kodi box with instructions for the user to configure it in such a way? What if they sold it with just a link to a Google search that had such instructions? What if they provided a script you could download and it would do the configuration automatically for the user but what they sold was actually a generic (legal) Kodi box?
At the end the only real difference is the advertising of that box - meaning if I would somewhat distribute a firefox browser with the proper links and call it the watch any media for free browser I would be in trouble.