Tangent: apparently contra DeMarco and Lister, I'd argue that "the worst" are often outright detrimental to a team or project. Which in turn makes me question the "math".
Being technically competent while also being perceived as merely neutral personality wise can lead to a lower overall qualitative evaluation, potentially affecting raises, promotions, etc.
I guess the lesson is that you (almost) always have to play the game or at least that playing the game well can yield many personal benefits.
My worst experience is someone who was highly prolific at creating enormous amounts of tech debt without the process in place to block it. We are still only about 50% through working off this giant stack of tech debt 2 years later.
If I didn't know any better, it sounds like you are just using the guy as someone to conveniently blame.
This is clearly someone who is working beyond their abilities, and needs help and mentoring.
This is not the person's fault, though, this is a management issue, and maybe also a cultural one, where people just assume this person "should know" just because they've been at the company for a long time, and mentoring would be "beneath" them.
A summary of the research: https://www.construx.com/blog/productivity-variations-among-...
I don't think there is anything wrong with the math, it is just that real-world productivity is not as easy to measure. The study didn't measure the "maintainability" of the resulting solutions, only how fast they were completed.
I think it really depends.
A senior that is 10x more productive than an intern or junior? That's perfectly fine, they are here to learn.
A mid-level dev that is 10x more productive than another mid-level? A bit of a red flag, and probably detrimental to the morale of the team.