I just looked at your wiki. The first thing that jumped out at me is that that number 2 and number 3 on the list for Europe are Flims and Laax. Flims and Laax are one resort, and the fact that they are listed seperately on this list tells me that either the methodology or execution of this study is flawed. For people more familiar with North America, this would be like compiling a list and having seperate entries for Whistler and Blackcomb. The fact that Flims and Laax appear next to one another in the rankings also suggests that the data is identical. Did that not raise any flags? Not if those conducting the survey did not have the basic knowledge to recognise the flags. That alone leads me to disregard this study's findings.
The study would also have more meaning if you told us something about the resorts at the top and bottom of the list. Why is Arosa tops? Why is Argentiere not green?
As for the broader question, yes I think about the "greenness of skiing". Snowmaking in particular causes me concern. Stricter environmental policy in Germany makes it very difficult to install new snow cannons, and that is harming what was anyway a struggling ski industry here. But if that industry is not sustainable, maybe that is for the best. I don't mind if as a result we end up with smaller, greener ski resorts.