Edit: I guess that was obvious considering this gnu screen announcement contains as much (or more) discussion about tmux as screen.
Also, the definition of one license is "more free" than the other is completely subjective and is wholly dependent on the perspective of the licensee.
That is just false. BSD has fewer restrictions. GPL has more restrictions. No subjective interpretation needed.
Not everyone agrees. Hence, subjective interpretation. Saying otherwise is just trolling.
Let's clarify: Technically, it allows the copy (distributed with the proprietary software) to become non-free, though the original and any other copies of the original are still free. Technically, BSD is more "free" than GPL to the first copier, even if not so to everyone else who obtains it from the first copier. The "subjective interpretation" then is from the point of view of the next guy in line.
No, it doesn't.
It allows non-free software being made incorporating the free software, but the free software remains free. It also allows free software with different terms than the original to be made also incorporating the free software which remains available under the original terms.
Yes, the BSD license has fewer restrictions than the GPL. That makes the BSD license a more permissive license, not necessarily a more free license.
The BSD license allows licensed code to be used in proprietary software but the GPL requires any derivative work to be licensed under the GPL thereby guaranteeing that the licensed code is always used in free software. Therefore, one can argue that the GPL license is "more free".
Freedom from oppression means that the oppressors are restricted, and you can't install your spyware and call it DRM that can't be legally removed. Freedom from coercion means that you can't coerce someone, and security researchers can live without fear of EUAL's or copyright licenses that forbid the disassembling of software. No 7-year-old girl will be sued because of art which is based on what I have made, and no one will be sent to prison because they dared to share a copy to a friend.
"freedom is not as Sir Robert Filmer defines it: 'A liberty for everyone to do what he likes, to live as he pleases, and not to be tied by any laws'. Freedom is constrained by laws in both the state of nature and political society." - John Locke (1632–1704)
Without it you do not have the mental yardstick to evaluate things properly.
To be fair, I have contributed code to Apache licensed projects (and in fact I maintain one). It still annoys me that it's not GPL licensed (the annoyance doesn't go the other way around for me, I am not annoyed when a project is GPL licensed).
Right now the world seem poised to enter another major war.
This i attribute to the generation of politicians holding the reins has not experienced full scale war up front and personally.
Similarly, one has to experience the depths of proprietary lock-in to be really able to grasp what is being attempted with the GPL.