If a system is extremely oppressive, as is the system of animal agriculture, is it possible to improve the system from within or should we abolish the entire system?
I certainly think that it is possible to change an industry by working “from the inside.” There are some animal organizations that own stock in companies merely in order to be able to have input in the way the company operates. As shareholders they get to vote or sometimes speak in company meetings. This is one way they effect change.
However, I’m not sure that’s the best allocation of resources if one wants to save animals’ lives, fight speciesism or carnism, or improve animal welfare. For example, encouraging people to eat a vegan diet is by far much more effective at reducing animal suffering than virtually any other form of animal activism.
Another example, if someone is strongly inclined to work “from the inside” then they could probably do much more good by investigating and exposing animal cruelty than by trying to change the system themselves from their inside position. The output from those investigations is extremely useful. Just consider the massive effects of showing the public video footage of factory farm investigations.
So, yes you can work “from the inside” and if you’re strongly inclined to do so then go for it.
But if you take a step back and logically think about this tragic situation for animals and you’re not willing to be an undercover investigator but you still want to make a significant difference for nonhuman animals, then it’s probably best to work hard at encouraging as many people to go vegan as you can.