I partially agree with you
Primary gold ore or Monazite and many other reserves of Bihar are owned by union of India not by Bihar state government so even if it’s mined it would be spent on Delhi Mumbai Noida Gurgaon etc not on people of Bihar who are the real owners of these mineral resources
But it’s also true if Bihar gets the ownership rights of its mineral resources then it would be one of the most prosperous regions in Asia just like Australia
Australia's main export is
iron ore, followed by their other most valuables exports coal, gold, and petroleum. These exports alone rake in $48.2 billion, $47 billion, $29.1 billion, and $20.3 billion, respectively.