Why would a drive shaft mount need to be replaced when a truck only has 16000 miles? on 2009 Nissan Titan

Considering buying a slightly used 2009 Titan truck with 16000 miles. It clunks when starting & shudders when driving - I thought it was the tires, but the dealers mechanic said they had to replace the drive shaft mount. Why would that go out so soon? It has a towing package & I'm not sure if it was over used by previous owner. Any thoughts?

it's still under factory warranty, so it must be no charge
to you. who knows? factory defect?