"Durable physical medium" protects users whose only access to the Internet would be through an ISP that has unconscionable Terms of Service, but who have access to postal mail.
I think the GPL is brilliant and useful, but I disagree with its philosophy here because it centralizes the hassle caused by lame ISP's. If you have a lame ISP, you can ask a friend with a decent one to download the source for you, burn a CD, and post it to you. Decentralizing this work means that providing source code does not become onerous even as the number of users (who want source) grows huge. The developers can spend most of their time improving the program, and less of it burning CDs.
My favorite open-source/free-software license (the Open Software License 3.0) makes it very easy: The licensor merely has to place
a machine-readable copy of the Source Code in an information repository reasonably calculated to permit inexpensive and convenient access by You for as long as Licensor continues to distribute the Original Work.
Those terms ('for as long...') remind me of another problem with the GPL, that you have to provide source for three years after you stop distributing the binary (or book or whatever object code you use it for). Three years is a long time in the computer world! Many websites do not exist for that long.
I recognize that sometimes it is better to centralize a hassle. Obfuscated email addresses in Usenet postings, or in mailing list archives, shift the burden of dealing with spam from the poster to every reader who wants to reply and has to type the correct address in by hand. But if the poster has a decent spam filter (e.g. bogofilter), or their ISP does, it would take care of most of the problem. Or, to reduce pollution, use electric cars (the energy is generated in a large central power plant, which presumably can afford good scrubbing technology, whereas a gasoline-powered car has to carry the technology (catalytic converters) around with it, which is much more expensive and wasteful).
However, with source code provision, I think decentralizing has advantages.
Copyright © 2017, Eklektix, Inc.
Comments and public postings are copyrighted by their creators.
Linux is a registered trademark of Linus Torvalds