If nobody suffers, why do you need empathy?
If nobody can suffer, what purpose is there in lessons that improve our life? There are people who would undoubtedly say that a world without suffering would be the best, so if people can’t suffer, there would be no further room for improvement by that criteria.
Experience and knowledge from suffering teaches us to improve ours and other people’s lives, but improvement usually means that we act in a manner that decreases the suffering of ourselves and others. If nobody can suffer, the experience and knowledge from suffering is meaningless, because there is nothing to avoid anymore.