I think I might be one of the people you describe, but I don’t think you understand the reason that people get offended.

I am not offended by the facts about factory farming, or that meat production releases methane. I am offended by the implication that someone will forcefully take away my ability to consume foods that I want to eat, and will use morality to justify it. Removing the freedom to eat meat is still taking away freedom no matter how you justify it and people will resent it.

If your goal is to improve the quality of life for livestock or reduce emissions from livestock, perhaps by changing the diet that animals are fed: nobody will have a problem.

As soon as you imply that someone’s way of life is immoral and their diet must be forcefully changed, you will encounter huge resistance.