The problem's not so much that they can fail—any method can—as that they can fail with anything short of overwhelming and sustained support, that is, they can be wildly popular and still have no long-term effect at all. Better to look elsewhere—no amount of "if we'd all just do it, we could fix this!" will change that.
Again, as a personal choice, fine. As an alternative to more-effective means, no. It's not "arrogant", it's an outcome-focussed stance fitting with observed reality and current scholarship.
[EDIT] "They" being "movements mostly based on changes in personal behavior patterns, at some significant personal cost or risk"