I can't answer for the parent but to me these two situations are not really comparable. Making self driving cars is cutting edge technology and I can definitely believe that having access to a competitor's engineering secrets could be a huge advantage. For something like fitbit I'm not so sure, it's mostly existing technology. I suppose "market research" can be valuable though, but the article doesn't offer enough details to figure out what that means exactly.

It's hard to know for sure without knowing exactly what Jawbone thinks has been stolen.