I am from a 4th generation wine growing family from Germany, and we have the exact same issues here. There is a global oversupply of grapes and wines. A lot of people in my region are struggling, my family included. Some experienced growers estimate 5-10 years until it becomes better for growers.

The trade wars, which some commenters suggested as a reason, are adding not as much to it as you might assume. I personally thing that it is more of a generational shift of habits.