While from a scientific point of view we can say that many living beings feel pain and that some living beings can also suffer, it should be noted with regard to our experience of human pain and suffering that the feeling of pain and suffering always has a strongly subjective component. Some people have strong defence and resilience mechanisms against pain and suffering, for example in war or natural catastrophes, as well as in the fight against pain in medicine. There is no objective dose of painkillers that must be administered to a person for the pain to stop. Pain therapy is an individual therapy.
That is why one has to be careful in judging pain and suffering in animals, especially when it comes to pain and suffering in animals living in the wild, uninfluenced by humans.
We can say with certainty that we humans inflict senseless pain and suffering on other living beings, especially on animals in industrial factory farming, and we do not need the intervention of a divine being to stop this. There are ways to keep and kill animals for food without causing them suffering or physical pain. This is, of course, contrary to factory farming and requires us to change our diet.
From a biological or scientific perspective, the feeling of pain and suffering has an important function, on the one hand in the evolution and preservation of living beings, and on the other hand in the development of empathy, for example. Suffering in particular is not a one-way street, but part of a catalogue or range of emotional reactions and sensations.
From my professional experience with the medical side of pain and the pastoral-therapeutic side of suffering, I consider the assertion that a world with pain and suffering is in necessary contradiction to a good world willed by a good God to be too simplistic.