Exoplanet science is not physics, it's chemistry or planetary science. By your logic prizes to teams who send probes to the outer solar system planets could also be given prizes.

Ok, so under what logic does ML become physics?

What's "exoplanet science"? The above are applications of knowledge of physics to astrophysics, as far as I understand it. Certainly they sound more relevant to physics than neural networks.

I would argue that the first measurements of exoplanets' existence is definitely physics. This was a leap in our understanding of the makeup of the universe.

Alfred Nobel's stated standard for a prize is:

"conferred the greatest benefit to humankind"

So while those things are cool and groundbreaking, I'd say they have yet to cross the threshold into "greatest benefit to humankind"

If you define "benefit to humankind" narrowly, and don't view gaining pure knowledge about the workings of the universe as beneficial to humanity, then most physics Nobel Prizes over the last few decades fail the test.

Detecting gravitational radiation from the merger of two black holes was an incredible step forward for our understanding of the universe. It will not practically change your life in any way.