>There isn't anymore low hanging fruit today, discovering novel things likely involves spending your early adulthood learning all the things our smart ancestors discovered as a primer to being able to understand what's left to discover.
Just the opposite. Discovery happens when your confined and forced to discover (be creative) to survive and evolve. If your learning from everyone before your not discovering anything, your just repeating history.
What I'm getting at is, if you want to expand humanities understanding of physics, you first need to spend six or so years learning everything that humanity already knows about physics. After that, you can spend a few years doing research or designing experiments -- usually alongside someone whose dedicated their life to the field -- which will then, hopefully, culminate in your tiny little contribution to the knowledge of humanity.
But, even just 150 years ago, you could have made multiple ground-breaking contributions to the world of science, or even developed entire fields of study.
Just the opposite. Discovery happens when your confined and forced to discover (be creative) to survive and evolve. If your learning from everyone before your not discovering anything, your just repeating history.