He tells me that their is massive oversupply of every single...

He tells me that their is massive oversupply of every single commodity. This surplus will continue for decades.

Everyone has own views but not every view is absolutely correct, even from an economist of Goldman Saches.
No point to argue something we are not sure, or probably no one can be 100% sure. The fact is share price has been played by market participants. Most of investors are just passive players, to identify buy and sell points are the key to success for retailed investors.
What I believe ARI is a good buy at current level, regardless of many negative sentiments.