Assumption is that animal industry will reduce if more people become vegan, and that has a big impact.
But I unfortunately agree, that the industry will likely not change until maybe at least 50% of population are strict vegans, or maybe even then, they will just try to make the rest of population consume more meat to never reduce the production.
Compressed air is about 0% air, you're correct in that, but nitrogen is a part of air so it's not it. It's butane, propane or other less flamable but worse shit, afaik