It tries to measure the defect rates between programming languages. To say it doesn't matter is too simplistic, in my opinion. I think matching the tool to the task is somewhat important, but often, as you suggest, you can get by with suboptimal choices and choose based on familiarity or esthetics. People would probably do better by spending their time learning how to think critically about code rather than learn a new language every year.
https://web.cs.ucdavis.edu/~filkov/papers/lang_github.pdf
It tries to measure the defect rates between programming languages. To say it doesn't matter is too simplistic, in my opinion. I think matching the tool to the task is somewhat important, but often, as you suggest, you can get by with suboptimal choices and choose based on familiarity or esthetics. People would probably do better by spending their time learning how to think critically about code rather than learn a new language every year.