Yes! I think this is a more accurate description. And this is exactly the intent of the licenses…i.e. they’re intended to maximize the freeness or openness of the material. I.e. not only do they ensure that the work remains freely available, but anything derived from it must also remain free in such a way.
And it makes sense that not everyone would want this. Anyone in the business of proprietary software would find copyleft licensing incompatible with their business model.
How does this apply to iNaturalist though?
The way NC licenses are presented, which I would argue is misleading (see this thread and this proposed diagram), is that they allow all use except for “commercial” use. As I have argued in this point though, this is not true…they exclude all sort of other types of use, including use in copyleft works, use by any organization, i.e. anyone other than individuals in Germany (and potentially more countries.) And then there is the additional issue of people erring on the side of caution because of the vagueness or ill-defined boundary of what exactly constitutes “commercial”, which discourages all sorts of use that is relatively certainly non-commercial, but the lack of 100% certainty precludes use by people who don’t want to deal with the possibility of problems down the line.
I think SA licenses actually do a better job of discouraging “commercial” use. You yourself gave a testimony of how and why you avoid them in your work, and this is going to apply to all but a few types of business models. A software developer can make money from copyleft software by providing support or implementing custom solutions on-demand, but they can’t successfully sell the software itself because it’s available for free (except if they sell it really cheaply and provide a convenient package, as back in the early 2000’s when some companies were selling linux installation CD’s in neatly packaged boxes and making some money off them.) And anyone could sell prints of a copyleft photo, but if it was much more expensive than the cost of printing and any added value of convenience, no one would buy it because it was also available for free.
So the SA licenses effectively limit commercial use. But they do so without any of the problems I have discussed above. There is no vagueness of what constitutes “commercial” use.
This is why I would prefer CC-BY-SA to be the default option. I would argue that it does what a lot of people think the NC clause does, but it avoids all of the problems that the NC clause brings, that people didn’t necessarily anticipate. The NC clause and licenses, I think are misleading, and I would prefer if they were not used anywhere.