I agree. What you say about avihimsā is an appropriate way to regards the environment from the point of view of the Dhamma.
The efficacy of the Dhamma is measured in terms of internal mental purity, with respect to the objective ideal of nibbana.
The efficacy of environmentalism is measured in external environmental purity, with respect to a subjective ideal of a utopian environment.
Avihimsā contributes directly to internal mental purity.
"Do not force others, including children, by any means whatsoever, to adopt your views, whether by authority, threat, money, propaganda, or even education." - Ven. Thich Nhat Hanh
"Whether I were to preach in brief, Sāriputta, or whether I were to preach in detail, Sāriputta, or whether I were to preach both in brief or in detail, Sāriputta, rare are those who understand." (A I 333, Sāriputtasutta)