Why does Islam allow killing certain animals? I’m struggling to understand the wisdom

Salaam everyone, I hope you’re all doing well. I’m from Malaysia, and it’s pretty normal here to kill house geckos on sight. But when a friend told me that Islam actually encourages killing them, I didn’t believe him at first. Then I came across a hadith about it and realized it’s true. But what I don’t get is why we’re not just allowed, but rewarded, for killing creatures that haven’t done anything to us. One reasoning I’ve heard is that a lizard helped fuel the fire when Prophet Ibrahim (peace be upon him) was thrown into it, but that doesn’t sit right with me. Why punish an entire species for something a few might have done? And it’s not just lizards-it’s snakes, crows, kites, dogs, and rats too. I thought Islam teaches us to treat all living things with kindness. What’s the benefit in killing them? Also, does this apply to all types of lizards? From tiny house geckos to komodo dragons, and even endangered ones like some iguanas? Same with snakes-many are totally harmless and can’t hurt you even if they try. I’m not vegan or anything, but I really try to be as humane as possible with animals. JazakAllah khair for any insights.