The researchers focused exclusively on developers in the R language ecosystem, and as far as I can tell they scope the claims in their paper to only the R ecosystem. For whatever reason, the headline and lede instead emphasize a piece of pure speculation toward the end of the paper (generalizing to other open source communities) rather than the actual substance of the paper (exclusivley focused on the R ecosystem, and not even claiming that their results fully generalize even to all R developers, let alone all OSS developers).

Here's why I think this work doesn't generalize: Academics and people who don't primarily identify as software engineers are over-represented in the R community, when compared against other open source projects. I think the set of answers you'd get from e.g., the developers of more traditional types of open source projects (editors, compilers, databases, games, OSes, frameworks/libraries, etc.) are fundamentally different.

While I'm on my soap box, the other mistake that researchers who study open source developers often make is focusing on very successful open source projects, and then implicitly or explicitly generalizing those results to the huge hoard of open source developers. (Implicit generalization goes something like this: Intro: there are so many open source developers -- understanding their motivation is important! -- Actual study: let's look at the motivation of contributors to the top 1% of projects -- Conclusion: we think these results generalize to other projects. Note that the authors of this study avoid this pattern, but the journalist doesn't.) But of course, the motivations of the vast majority of OSS developers are going to be fundamentally different from those developers who have built extremely successful and high-profile systems.

Overall, I think this is a really nice and interesting paper about the R ecosystem. I just wish the journalist had chosen a different headline and lede.