I would never have had the opportunity to read the DOOM source if JC had insisted on using BSD, because, as JC tweets, his business partners at Id soft would not have gone for it. ipso facto the GPL + Id + JC are responsible for this privilege being available to us all.
The relevant implication in it hypothetically having been BSD is that he would have convinced his partners, not that its usage would have made the project never happen.
i don’t see that. i see carmac reminiscing as, wouldn’t it have been nice if this had happened rather than that, while clearly acknowledging that his business partners would not have gone along with ‘that’. the implication I draw, having no more info than these tweets, is that, after some discussion, JC and Id compromised on using the GPL to license the DOOM source, versus not releasing the DOOM source. The GPL allowed wide general availability of the DOOM source, which Carmac wanted, while being acceptable to Id’s business needs as Id saw them at that time.
You're correctly inferring what JC is saying, but missing the point the other poster made; which was to imagine that history had gone differently, BSD was approved as the license, the source code was still publicly available, and how that would have benefited (or been detriment) to the widespread usage of the source code.
i'm dismissing the point the other poster made, because what I see as important is what actually happened. what I see as important about what actually happened is that the BSD license was incompatible with the situation, and if only the BSD/MIT whatever license was available, no one outside of Id or one of their contractors would ever have seen the doom source. I see that availability of the DOOM source as a great good for humanity which wouldn't have happened in a world where no GPL exists.
Can’t it be rereleased with a BSD license now if the copyright holder agree?
Copyright holder can do anything he wants with his code, so yes, John can rerererererelease his own code under different license. However, you cannot do that, even if the copyright holder told you something. He may change his mind tomorrow, or in a year, so you will have no legal ground for this act of piracy then.
Incorrect, there is zero about the BSD license that would've prevented you from reading the source if it was released with the Free-er BSD license.