That is such a weird way for people to think about masculinity.
If masculinity is something that should resist manipulation, then it cannot be defined behaviorally. Such a definition would mean that you must adhere to certain behaviors in order to be described as masculine.
Masculinity for me is attitudinal. Resistance to anxiety. Physical strength. Intelligence. Mastery over emotions. Perseverence. A willingness to fight to the death if necessary to preserve something held inviolable. Circumspectness. The ability to smile and keep moving even when in pain and under pressure. Respect for those who are not strong enough to demand it. Hard work. A desire to improve one's station in life, or that of his children.
I feel that this paints a more dynamic, more useful picture of masculinity than "football, dirt, beer." And I should be explicit: I recognize that some people do see those activities as masculine. I'm not disagreeing at all with your assessment there. I just don't think they capture the essence of masculinity, nor have those things historically been the definition of masculinity throughout human history.
That environmentalism may accidentally be pressing those same buttons is quite unfortunate, but not unexpected to me. We see things like rolling coal as a deliberate attempt by some men to "combat" what they perceive as non-masculine green living, and there did seem to be an attempt to spin the fracking debate into a gendered issue. Ideally we'd have grown past this as a society, but I guess people are going to be people whatever the age.
I personally have always been pretty comfortable violating gender norms on these types of issues. The idea of not doing things I enjoyed just because it was supposed to be "for girls" always struck me as absurd. Or conversely, doing things I hated (getting dirty, playing football, drinking beer) just because that's what men do and you want to be manly don't you?