We as an industry have no objective measure for what is and is not a good program. Therefore, we have no objective measure for who is good at programming.
If you ask me, a good program is one that is documented accurately and thoroughly. So a good programmer is one who cares enough to document well, and has enough skill to do it with precision, speed, and with good judgement.
Of course, being a good scientist or mathematician requires the same skills: know who you are talking to, what they already understand, and why your work matters to them. And be obsessive about doing it the right way.
There is virtually no evidence that program documentation leads to "better" programs. In fact, there are many people that will maintain that the need for code documentation is evidence of a "bad" program.
Regardless of whether you subscribe to this theory or the opposite, there is no "objective" way to differentiate between these 2 spectrums.
I am telling you what a good definition of a good program is. Of course there is no evidence that my definition is the same as your (unstated) definition. You can disagree, but this has nothing to do with evidence.
Of course, being a good scientist or mathematician requires the same skills: know who you are talking to, what they already understand, and why your work matters to them. And be obsessive about doing it the right way.