I suspect we talk about the GPL as programmers because the relative freedom level of a software license matters far more to us than it does to actual end users. Restrictions on what you can do with the source code only matter if you're both interested in and capable of modifying that source code. On a practical level, the Average Joe is "locked out" from modifying an application's source code by virtue of not being capable of performing that modification, not by the license. I have a lot of non-developer friends and acquaintances who use LibreOffice, and I can assure you that they're using it for the "free as in beer" aspect, not because of a philosophical attachment to free software. For most end users, freedom is contingent on data portability, not license terms: if I can open my word processing document or Photoshop file, it doesn't matter to me in practice whether the editor is open or closed source. If the application stops being developed, I can move to something else with minimal pain.

But if we're talking about tools for a developer audience--like RethinkDB, and frankly a whole lot of other open source software--then developers are the end users, and so the license really does matter. I've long thought that one of the strengths of the GPL is that it's more restrictive from a developer standpoint, rather than less. If I was trying to build a company around open source software, the (A)GPL would be attractive expressly because it makes it more difficult for competitors to build on. If the company goes away and there's no way for someone to buy a commercial license with a different set of restrictions, that can become an issue, as we've seen with RethinkDB -- but the (A)GPL isn't necessarily an impediment to strong community development, as we've seen with, well, a lot of other software over the last two decades.

> because the relative freedom level of a software license matters far more to us than it does to actual end users

Nah, it's not that simple.

Ever saw a giant chorus singing "oh almighty developers please make this and that" for tiny features? I think every other product support forum is just like that. And I also saw situations when someone on the outside had hacked features that weren't provided by original developers. Both free software projects and proprietary software.

So freedoms actually matter to the "common folk", they just don't consciously recognize that and surely they don't know the terminology.

Sure, I get that. But that makes it a very opinionated form of free and open. While permissive licenses like Apache and MIT do have terms, they are much more akin to saying "here is a thing I made, and I'm sharing it with whoever wants to use it and whatever they want to do with it". Whereas copyleft licenses are more like "I'll share this with you, but you have to use it in accordance with my beliefs".

While I accept that the OSI definition of "open source" is pretty much universally accepted and probably isn't going to change, I personally don't really feel like copyleft should qualify because of that level of control it exerts.

That's a good point. Copy left and open source have very different targets and just happen to share many characteristics.