Too often people cite truisms to explain behaviors they find too inconvenient to contemplate and change. "It's the cycle of life," "everyone has a right to their opinion," and "it's natural so it must be good," are among the most. The religious will fall back upon "god works in mysterious ways," or "it is god's plan."
All these are aphorisms deserving of elimination, as they simply equate to "I don't have the time to think about the horror, and I don't want to take time out my life to address it." Billions of humans have become part of a society which compartmentalizes our lives away, in part to cope with the egregious damage we are doing to the planet and to other sentient beings.
To be sure, we are as imperfect as the matter we are made from and we need to cut individuals and society a little slack for needing some time to parse the information. Still, it's important to realize we are on borrowed time and each day we should make an effort to understand the world a little better. Human beings are the apex predator and apex occupier of planet Earth, so we should also be the apex contemplator and apex steward as well.
Of course, each of us can do our own part in our own way, but only when the masses unite under a flag of progress does anything significant get done. The cycle of life may indeed happen, and yes many will be hurt in the cycle, but we as individuals can ameliorate the suffering. Others may not deserve persecution for sharing their opinions, but bad opinions should be put in their place as misinformation and malevolent when the facts contradict their arguments. Nature may be a starting point for stable existence, but human ethics should overrule nature's cruelty when it can and when it makes sense. There is no holy plan, only human plans that can be rethought and adjusted over the long-term to better outcomes, the goals of which also need constant refining.
In the end, reason, compassion and desire are the tools of humanity we need to strengthen to get the ever-changing job done. Perhaps a better aphorism to start with is one Temple Grandin suggested: "Nature is cruel, but we don't have to be."