Should my nephew become a teacher?

(I'm in an Asian country, I cannot elaborate due to very many personal and professional reasons.)

(Apologies for poor English)

My nephew (17yo) specifically, wants to study Astrophysics, whether as a major or minor, to at least Masters before finding some related job that he could use the masters at (not necessarily physics related). He's not hoping for an academic job, but simply wants to learn astrophysics, his passion, to masters.

His parents, specifically my older sister, wants him to apply to a government teacher programme. This programme would auto let him become a teacher, and becoming a gov teacher lets him be qualified to have sponsored studies.

My nephew: graduate -> masters -> job. My sister: graduate -> programme -> teacher -> masters

However, my nephew does not want to become a teacher, as to even qualify for the sponsored studies, he needs to: work at least ten years, consistently high quality works, and apply for a field the government may think is beneficial for him, the school, or the country.

Since he likes Astrophysics, and the country does not have a single development or needs in that field... He says, in his own words, "I'll live and die never touching the sky I yearn for." Quite dramatic, but since this is his own future we're talking about, isn't that far out of left field.

I admittedly also had some hand in him being a lover of astrophysics, with me often taking him aside during family functions to talk about various theories I happen to remember or stumble upon that morning.

The strongest contender my nephew is facing during this very heated and loud family argument is the fact that my family has very strong and plentiful connections in the education sector. This is the reason why I cannot tell you my exact country. However my nephew, just like me (heh), refused to use this connection and wants to pave his own path that his family had never seen.

He came to me hoping to have me support him but I do think my sister makes some sense. Even if we had connections, our specific branch of the family does not have much money, and certainly could not support him all the way to masters, especially since there's no local uni that offers physics and especially not astrophysics course which meant he would have to go abroad. But my nephew is also a good and hardworking student, all of the subjects he needs to apply for the course — he had passed with not only flying colours but also almost perfect scores. He assures me that even if he could not get scholarships, he would work himself to the bone while studying to support himself as much as possible.

If it were anyone else, I would have immediately supported my sister. But since it's my nephew, I know he is responsible and diligent enough to strive for what he actually want. I heard there's an unspoken diversity choice for many unis and scholarships, and since not only is my country filled with minorities, but my nephew's race is the most minor of minorities (less than 500 alive rn, and likely even less), maybe he'll have a higher chance of getting offers?

Tldr; Should he pursue his childhood dream, or should he pursue stability?