It's reasonable on a secular level too...
1.) does everyone have a right to life?
answer: yes, objectively
2.) are feoti people
answer: depends. Let's answer the logic of what answer you'd give.
2a.) is it a person if it doesn't have feeling/emotions/consciousness/etc?
2b.) is it a person if it will have those above later?
depending on your answer to those, then you would either agree or disagree with it. For me, it's extremely reasonable because there's no reason to say that something that will objectively, inevitably become a person unless stopped should have their right to life taken away from them.