A side-note: In the article you mentioned, I noticed they said “Here in our South London micro-community we have no sequoias” which brought to mind another article I read last year “Giant redwoods: World’s largest trees ‘thriving in UK’”.
Regarding the overall topic, I appreciate what’s been posted by others here and think we need to do as much as we can of all of the above. You, @jme, are already doing such an important thing by studying and preparing for a career as an ecologist - that’s fabulous! You are definitely not alone in your concerns, look at your classmates and teachers, in addition to your fellow iNaturalists. There are times we need to comfort ourselves to regain strength, and we also need to use our discomfort to make necessary changes.