By that reasoning, fruit is not in a biologically obligatory symbiosis with the animals that eat it. There are many cases of fruit falling to the ground uneaten and forming a new plant near its parent. Those plants eke out an existence just as feral pigs do.
Yes, and this is an undesirable result. You can eke out an existence with no legs, but it is not the preferred state of things. You’re just debatelording now.
Yes, it’s possible but undesirable for both pigs and fruits to survive without assistance from humans. In both cases, that assistance is offered because humans eat the creatures they assist.
You still haven’t explained why this relationship is good for fruits but bad for pigs.
Because “good” and “bad” have nothing to do with my point, which is about purpose. The purpose of fruits is to be eaten, that is their explicit function. While the pigs get some benefits (in principle, in practice factory farms are horrific places which are absolutely less desirable to the pigs than the wild) they do not volunteer themselves for slaughter the way plants volunteer fruit for consumption.
Being eaten is the core benefit of fruit, and all else being equal being eaten is preferable to not. All else being equal, the pig benefits more by not being eaten, and just living peacefully on a farm.