The GPL is of course completely commerce-friendly, as it permits anyone to resell the original or modifications to it. What you're asking for is a license friendly to proprietary software[1].
Why on earth would they want to enable someone to close his modifications to RethinkDB? How does that make the world a better place? How does that encourage the growth of RethinkDB (vice the proliferation of closed, proprietary forks of RethinkDB)?
[1] Which is to say, user-hostile software. Users should be free to use, modify & distribute software.
Proprietary software is not by definition "user-hostile," and hyperbole like this does much more harm than good to people like me who would like to see more open source and less proprietary software in the world simply as a matter of principle.
I can see why you're sometimes labeled as "fanatics" and "zealots". You speak in religious-like absolute terms and use circular logic to "prove" you're correct. The GPL's biggest enemy are its most ardent supporters. Truly.
I disagree. Most of those are things that most users don't give a damn about in most cases (because they're meaningless unless you have certain unusual skills), which means they don't make for a sensible definition of "hostile".
Do pirate bay support your statement or proof that it is wrong? Maybe it just that "most users don't give a damn" about copyright, and as such don't care if what they do is legal or illegal with current copyright laws. In order to care about copyright licenses, first users need to care about what happens when they don't follow it.
So you care more about having the entire pie, than about how much pie you have?
If you have a license that "permits" commercial sales in a way that by design makes most business models completely unfeasible... guess what? You'll only get contributions from those with one of the handful of blessed business models. Which will work or not depending on what sorts of businesses models your project is suited for.
Copyleft works fine for things like the kernel that are complementary to tons of different expensive things and nobody cares about otherwise. Permissive works well for Postgres.
At the same time, you're arguing that you should be able to take the work they've done, add to it, but not give back, despite having received a HUGE base to start with.
Why on earth would they want to enable someone to close his modifications to RethinkDB? How does that make the world a better place? How does that encourage the growth of RethinkDB (vice the proliferation of closed, proprietary forks of RethinkDB)?
[1] Which is to say, user-hostile software. Users should be free to use, modify & distribute software.