The only freedom GPL denies a developer is to close up software that was once free.
You can't "close up" software that was free. The software remains free.
The only freedom the allegedly "more open" licenses give developers is to deny freedoms to their users.
It gives developers the freedom to create an aggregate product without also releasing their own code under the GPL, allowing them to pursue a business model that they feel will fund the ongoing R&D necessary to produce that product.
For the users (and software freedom is about them), those licenses give nothing.
If users do not feel that a product does not provide a fair trade, they are under no obligation to purchase or use it, and the original code remains to do with what they will. However, as indicated by vast market success, users do feel that these licenses and the products produced using them do provide something of value.
No, you can't take a BSD-licensed program and make it non-free. What you can do is use it as rev 1.0 of a commercial closed-source project and dump resources into improving the closed fork and capturing share from the original code.
What GPL prevents that BSD doesn't is closed forks. Obviously some people don't care about closed forks --- some people may even like them on principle --- or nobody would BSD-license anything.
You're arguing that users don't believe the current situation is a fair trade, and would rather enter into a GPL quodque pro quo agreement if they were not restricted by the purchasing department?
Well -- I for one am happy with the licensing status of Mac OS X, and think I've received a perfectly fair trade.
Many users would be happier with technologies different from the ones endorsed by their managers (frequently after vendor-paid trips to vendor-sponsored events) and anointed as corporate standards that one should not break if one really likes his/her job.
My wife had to build an intranet on top of Sharepoint because a PHB said so. I have to read my e-mails off an Exchange server because corporate IT finds it nice. Far too many servers are Red Hat while I would prefer Debian (I am a fan of APT). Perhaps you have to make your presentations on PowerPoint for Mac, even knowing how much better they would look with Keynote. Life's not perfect.
And, while I love the NeXT side of OSX, I find the Unix side far too early 90's for my taste ;-)
You can't "close up" software that was free. The software remains free.
The only freedom the allegedly "more open" licenses give developers is to deny freedoms to their users.
It gives developers the freedom to create an aggregate product without also releasing their own code under the GPL, allowing them to pursue a business model that they feel will fund the ongoing R&D necessary to produce that product.
For the users (and software freedom is about them), those licenses give nothing.
If users do not feel that a product does not provide a fair trade, they are under no obligation to purchase or use it, and the original code remains to do with what they will. However, as indicated by vast market success, users do feel that these licenses and the products produced using them do provide something of value.