I apologize that my original comment was lightweight and lacking sources. If I make such a claim, I should back it up with sources. I'm about to fall asleep though, and I don't remember where precisely I saw it.
Within the last couple months, there was a pretty big discussion featuring BSD licensers vs GPL licensers. If I remember correctly, the GPLers were saying that by using BSD, one enables software freedoms to be taken away, and therefore BSD and MIT licenses should be strongly opposed.
I think it is the fact that some companies create crippleware open source project where parts of the core are open source and additional key parts are licensed under a sub-license that requires payment. Also, MIT and BSD doesn't enforce you to share added changes, fixes or additions to a project because of this - thus, hurting the open source community by the project not gaining (possibly) important or significant changes.
From a company standpoint, this makes sense if the parts are large and costed a lot to develop. Some companies eventually make these parts available eventually, some don't though - possible because open sourcing something that you initially charge for, could piss some customers off when they realize that they could have gotten it free.
These "discussions" happen all the time, so I have no idea which one you're referring to, but the only reason anyone on the GPL side "gets mad" is because those on the BSD side whine childishly whenever someone puts something under the GPL.
As opposed to GPL & Toejam afficianados alike, who basically claim any license except GPL3 is the work of the devil, because I, a developer, dare to give someone other downstream developer, the choice to distribute derivative works how they see fit.
GPL perponents always claim its about "freedom". But it's one specific type of freedom, to the exclusion of all others.
Actually, at the moment, it's about the freedom of the developer of software to choose the license their code is offered under. GPL advocates make arguments for use of GPL. BSD advocates, as you've just demonstrated, prefer ad hominem attacks on RMS when they don't get what they selfishly feel entitled to.
GPL-like licenses are designed to protect the freedoms of users at the expense of the freedoms downstream developers (or repackagers) would prefer to have. A Red Hat customer always gets full source code for all the GPL'ed software Red Hat sells them.
BSD-like licenses emphasize the rights of downstream developers (and repackagers) at the expense of the freedoms of their users. A Cisco user has no access to all the originally BSD-licensed software inside their routers.