Why does caregiver and caretaker mean the same thing?

Caregiver is healthcare related, you are a licensed professional that gives care (hence caregiver) to the individual, whether private practice, patient (acute care), or resident (long term care). Caretaker is property related, you take care (hence caretaker) of a certain property as hired to do so etc.

Doesn't mean exactly the same thing. A caregiver gives care to a living creature, usually a human, while a caretaker takes care of property.

It's a great example of how aweful the English language is. Whether you're taking care of someone or giving them care, Americans will find a way to shorten the amount of words they have to say

caregiver, gives care to a person caretaker, takes care of a property or a home

you take care of someone or thing. You give care to some one or thing