Sorry I was procrastinating and I didn't realize we were still strongly contending. Here is a better response.
You have a very small sample for a real-world basis.
Your first argument defending BSD's allowing source closing was, "this is not the norm, and when it does happen it requires people to be super evil". My counter-argument was essentially, "even if it's not the norm, whenever it happens it's bad and doesn't require everyone to be super evil, unless you think the ZDaemon dev team is super evil, which I doubt you do". Now you're ignoring my counter-argument, and simply restating the fact that it rarely happens. I'll then restate that its rarity (not that I'm yielding this point, I'm just too lazy to find a list of apps that closed up and killed their communities) doesn't matter, the fact that BSD allows source closing and thus community death sucks and sucks hard. GPL doesn't allow this. GPL wins.
Plus, I don't think it was the closing of the source that caused - well, whatever you claim it caused - so much as the extreme reaction to that process.
FWIW, this statement is basically the same as, "I don't think it was the fact that I held a pillow over his face that killed him, I think it was the fact that his brain responded to oxygen starvation by dying and thereafter stopped sending the signal to his heart to beat". Causation is a thing.
I'm guessing you're trying to shift responsibility from the devs to the community, but this actually makes my point. Source closing was a huge blow to the ZDaemon community, the outcry was sharp, and the community ultimately fractured.
After all, if it was the closing of the source, where's all the ZDaemon 1.06 forks?
It can't be forked because it's illegal. Or I guess to be more specific, it can't be forked legally.
But this is kind of a disingenuous question. Odamex is for all intents and purposes a ZDaemon fork. It just had to go way back to avoid the Raven code, which was incorporated due to more license ignorance.
It seems to me, that the only thing the GPL would have done would have been to chase away the existing developers on the project (who were getting tired of the issues associated with having all the sources in the wild), leaving the project to die.
Given the strength of Odamex development relative to ZDaemon development (up until recently, ZDaemon 1.08.x lasted longer than Odamex' entire lifetime), I would say that ZDaemon lost GPL devs to Odamex. If your argument is that source closing preserved ZDaemon's dev interest, my counter-argument is that keeping the source open would have attracted more devs only interested in contributing to open projects, and my evidence is Odamex's prolific development history compared with ZDaemon's relative barrenness.
Additionally, (stipulating that ZDaemon doesn't steal code, which no unbiased party can currently verify), were ZDaemon GPL it would have access to the deep pool of features represented in the GPL source port community. Therefore, not only would ZDaemon currently have more dev interest and activity, it would also have more features available to it now and in the future as the GPL source ports continue to innovate independently.
GPL 'upgrade' clause. You're putting a version of the code into a new license. This seems to me to be relicensing. We'd be pointlessly arguing semantics, but GPL2, GPL3, future GPL4 (which seems inevitable) seem to me to be separate licenses. Call it a revision all you want, but there's a lot of variations between the licenses.
I'm not really trying to argue semantics, I'm trying to argue actors. The only actor who can license or relicense code is the owner. Non owners cannot do this. Your argument is that licensing one's code under the GPL allows someone else to use your code under a different license. This is utterly, entirely false, and this fact has been repeated throughout our discussion. GPL neither implies, demands, nor enforces a owner's loss of control over his/her code.
BSD vs. Linux stuff
I'm in the awkward position of not really caring about this point, but feeling compelled to explore it nonetheless.
Obviously early BSD vs. Linux competition is a complex topic. You can't boil down BSD's failure to the AT&T lawsuit anymore than you can boil down Linux' success to the GPL. There are simply no stats, there are no charts documenting developer exodus from BSD due to the lawsuit, or developers flocking to Linux due to its license. Throughout our discussion I've attempted to hedge by saying that I believe a major contributor to Linux' success is the GPL, because a GPL project can never be closed source. This is more attractive to contributors than the BSD license because it means they won't contribute code on day one and watch the project maintainer close the source on day two.
I do think you are trivializing the SCO lawsuits. SCO sued multiple vendors. SCO implied that even developers and users might have committed copyright infringement. Many companies paid licensing fees to SCO. Many companies competing with Linux found ways to fund SCO's lawsuits. They were a pretty big deal at the time.
Finally, I'll point out that the BSDs and Linux are pretty rare birds. Your average software project has 1 dev, and is probably < 10k LOC. Scale and interest level would mitigate the damage from FreeBSD trying to close its source; a fork would be pretty immediate I imagine. But for a smaller project with a non-dev community, source closing can be fatal.
A lawsuit against an OS is a bad thing. It takes a long time to recover from that.
Additionally, the GPL wouldn't protect against a lawsuit, much like it had not protected against SCO's lawsuit. The shit still hits the fan.
Agreed, which is why I'm puzzled by your seeming lack of acknowledgement of the seriousness of SCO's lawsuits.
You'd have better luck attributing Linux's success on that it written from the ground-up as an open-source OS. Which, after the debacle with AT&T and BSD, was appealing to many people.
Not only that, the assurance that it would always be open was very appealing as well.
It seems silly to me to try and enforce the morality of code-sharing (something which isn't detrimental to another person's health & well-being) by legal document.
Well, I don't want to make a "moral" argument; I feel like that implies God will strike down devs who close their source code haha. I'm saying source closing harms communities and kills code reuse. Although I do personally think that's bad, I'm willing to entertain the idea that the premise is wrong or that communities & code reuse don't really matter. I doubt I could be convinced though ;) .
Like you said later in your post, programmers will write software, one way or another. Not all of them will share.
I think that's a shame.
Granted, we might still have Tenenbaum, Torvalds, etc, develop OSs, but they had something to mimic. In the world we live in, this was UNIX.
Could you imagine Linux if it were based off MS-DOS?
To be honest, I couldn't care less about UNIX or Linux or MS-DOS. I used to have strong feelings about OS design and philosophy but that's really fanboyism. But FWIW, it's really hard--some might say impossible--to come up with something completely new. Even if we didn't have implementation details of UNIX and the POSIX standard to go by, surely many pieces of UNIX would have found themselves in other software, one way or another.
But again, I don't really care. I think Android is pretty cool, but despite being Linux, it's basically nothing like UNIX.