Tbh it sounds like you're guilt-free either way. You're saying that it doesn't matter at all to you when your actions harm others. You would like to be able to say they didn't, but don't feel guilty if they do. Also fwiw as many people who have tried it will tell you, there is a gain in acting selflessly, and it's better than the gain from acting selfishly. The idea that altruism is for suckers is actually harmful to your self-interest.
Human behavior is economic behavior, which is a fancy way of saying "people do things because there's a perceived benefit to doing so". Altruistic behavior usually carries at least a social benefit, besides the "I did good" feeling which is also a personal benefit. Blaming someone for something outside their control and saying that they're always to blame no matter what nullifies both of those incentives: you stop reaping their rewards.
This is a good example: if you're still shamed despite altruistic behavior, why would I possibly keep making sacrifices that I gain nothing for (including feeling good about having done them) when I can go back to my VASTLY more rewarding hedonistic lifestyle?
If you put someone in a situation where they're supposed to feel shame no matter what, they're going to become 100% insensitive to it in record time. In other words: yes, I am guilt-free because there's no other possible state under this framework of inescapable blame.
I think you are too focused on the individual. Reducing your personal meat consumption, your personal emissions and so on is nice and all but it is not going to be enough. You are also embedded in a number of social structures and institutions and those will have to change too if we want to be able to claim to be "guilt free" and those changes require personal involvement.
Individuals tend to focus on the individual. Trying to change everyone's routine is like trying to push water upstream. You'd be better served by targeting a message to the Brazilian people that they should protect their natural resource.
