They are protesting because:

1. Construction will require clearcutting forest.

2. The factory will use large amounts of water and is being built in a region where water is scarce.

3. The factory will use solvents and paints which can cause groundwater pollution.

4. The local population is opposed to construction on environmental grounds, yet it seems construction will proceed anyway.

Of course, there are also people who are opposed to Tesla or the car industry in general, for both good and foolish reasons. I'd wager Musk being an outspoken anti-Semite and Nazi sympathizer doesn't go over well in Germany.

It's shitty reporting, plain and simple. Even Wired got it right.