There were a lot of people in the older thread about the patents stuff saying things like "well, are you ever going to sue Facebook?? You don't need to worry about the patents stuff".

But consider this: Facebook do something disastrous, like leak a bunch of private or financial data and it affects you really badly. There's a class action against Facebook. Now you can't join it, because you don't wanna rewrite your app without React to ensure Facebook can't counter sue over a patent that may or may not exist on React.