Eli5: Why do you use “they” for non-gendered speech instead of “it”?

Question

I’m not a native speaker, but as far as I understood, for singular objects and animals “it” was used. Why use “they” for individual people then?

In: 1400

Answer 1

Because ‘it’ feels very dehumanizing for a lot of people. Some people do use it/it’s pronouns, but they/them is a lot more common