I haven’t heard anything about David Attenborough talking about plant based stuff so I won’t dispute it but he did help found and fund the zoology museum in my town, one that specifically tries to educate people on the dangers of climate change and making species endangered. From what I’ve seen of his filming they’re pretty conscious about not leaving any waste behind too.
They do something fun with this in the three body problem. It’s amazing and makes a ton of sense but in the real world the application will probably be a lot cleaner.