He is being presented as a person who is being tasked with writing entire code bases and the same job as a senior developer. Even if we give him the benefit of doubt and assume that he is being paid handsomely (which I doubt since we are all very well aware of the mentality of such people whose sole goal is to use AI coders to pay as less as possible, none if possible), the responsibilities involved in this is a full time job, not the part time job most high schoolers do during summer time. Even then it is not "common" for high schoolers to work unless you have never left US. In many places, there are some that do unfortunately do need to work due to economic reasons. But rarely outside of US it is presented as excellent work ethics and patriotism. It is more common for people in mid to late university years to start working as "interns" not full time developers. Also see:

https://www.un.org/en/global-issues/children#%3A%7E%3Atext=The+Convention+on+the+Rights%2Can+earlier+age+of+majority.

"The Convention on the Rights of the Child defines a "child" as a person below the age of 18, unless the relevant laws recognize an earlier age of majority."

So if you are going to boast about a kid who is producing massive code bases, at least say something like "wow he is still not eighteen but look at what this kid is doing", do not try to present that as the new norm. That is just pathetic greedy skill-less, spineless wanna-be intrapreneur behaviour.

Most people turn 18 during the last year of high school, which means that there is a very significant chance that the dev in question is still covered under child labor laws.

Maybe it is because I grew up in the North East United States, but when I was in high school, my classmates only worked seasonal or afternoon jobs.