I believe that Harry honestly cares about the environment. I just don't want to be lectured by people who live in huge homes and travel extensively. That criticism is not only aimed at Harry, I feel the same way about statements made by Charles and William.
Emma Thompson flew from Los Angeles to London to attend a protest about climate change! Could she not just have posted a message of support on social media?!
There are all sorts of niche markets for travel. Some people go on cookery trips to Italy, wine-tasting trips to France, battlefield tours or religious trips to shrines. So I suppose some people will fancy going on eco tours.