That's source-available. What's with people in this HN thread knowing full well about the open source definition but advocating for this confusing use of the t

That's source-available. What's with people in this HN thread knowing full well about the open source definition but advocating for this confusing use of the term anyway, don't you strive for clarity and ambiguity-free expression when talking about something? And also... what is the link between unreal engine and this text from RMS about the different philosophies behind the Open Source and the Free Software movements?