Well, they already are working on the next expansion pack and game pack. Before seasons, people either wanted seasons or university. University is the 3rd most requested expansion pack. So, they probably are working on that. Plus, farming is more of in the past. I live near the "country" where people have that southern accent and are all about horses.
Farming is more than just animals. Farming is growing crops, produce, food, raising cattle and other animals. Another reason farming probably won't happen is because in farms, they raise the animals usually to kill them for food to sell. Unless you want that to happen, it's not really liable. Plus, farms nowadays are usually run by machines.
Just another thing that makes me think a farming expansion won't happen is because farming in some way was introduced into The Sims 4 through Seasons. The gardening overhaul and gardening career might be the closest to a farming expansion pack. Maybe they might add farming in a game pack, but an expansion pack? Not really.
It seems over the top to do a whole expansion about something that nowadays is less common. Plus, why would they add animals to another pack after what happened with My First Pets Stuff? All of those things should have been in the Cats & Dogs expansion pack. I think they might be scared to do something else animal related.
