It can both be true that deforestation isn't important to Brazils meat industry but that people mostly burn down forests to create meat. Just means that we could stop the deforestation without much consequences, which is a good thing.

You are correct. Most of the deforestation issue could be fixed with better law enforcement, mind you not just "harsher" enforcement, part of the problem is some previous governments went overboard with it, bothering people that weren't doing anything illegal. Sadly the current government fixed it by doing the opposite (enforcing too little).