The title of the vid is "Where will MU stock be in 2024 and beyond?" but you did not give any numbers on that. What do you think a reasonable range might be on the stock price?
The spending is granted if you believe Nvidia in their narrative about demand for datacenter and AI not dropping anytime soon. All future Nvidia's datacenter/AI GPUs will have some form of HBM memory. After HBM3E it will become HBM4. Investing now is important to stay competitive.