This is a powerful no-true-scotsman here. In my experience, the vast majority of people espousing technical solutions to climate change are barely aware of trade-offs if they've considered them at all. Externalized costs are primarily talked about as those imposed by fossil fuels etc. The costs imposed by environmental action itself are not so commonly considered.
> This is pinning all the woes of a particular marginalized group on the environmental movement...
The article simply pointing out that environmentalists aren't really helping here. Increased demand for cobalt and coltan is extremely harmful to certain groups of people who don't have a particularly loud voice in any segment of the environmental movement or the renewable energy industry. No one kills over rocks that have no value. By driving the demand for these minerals, unrest is increased in this region.
It's kinda silly to assume ~all~ environmentalists are fighting for these groups of people when the interests of many segments of the environmental movement are directly opposed to them and the article itself provides examples of environmental groups attacking them. The world is not black-and-white. People with good intentions can harm others.
I don't particularly like language criticisms, but word for word I think there is a lot more meat in your original comment than in this article.