Some people and their religions, hopefully, weren't inspired from some heavenly source. Religions that sacrificed children. Religions that cut out people's hearts on altars dedicated to their gods. Religions that threw people into volcanoes to appease their gods.
Even in the Bible, the Israelites were supposed to keep the Sabbath. A person could be stoned to death for breaking the Sabbath law.
But Baha'is say that somehow the story about Abraham taking his son to be sacrificed got changed from Ishmael to Isaac?
The resurrection story in the NT got changed by Abdul Baha' to be completely metaphorical, so Baha'i don't believe them as Christians have traditionally believed them.
I have no problem believing that people have invented their own gods and religions. They've shaped them to fit their culture. Religious ideas and concepts of gods and God have evolved. Today, we can take the best of religion and get rid to the rest. By doing that, how different would the outcome be as compared to what the Baha'i Faith says?
Except, what if we do that to the good and the bad from the Baha'i Faith too? I don't think Baha'is would say that is possible to separate any of the Baha'i teachings, because, supposedly, they all came from God as revealed by Baha'u'llah. But, essentially, that is what Baha'is are doing to all the other religions. Baha'is take what they say is the "best" of the other religions and gets rid of the rest. Multiple Gods or no Gods? Gone. Avatars/incarnations? Gone. Satan? Gone. Reincarnation? Gone. Resurrection? Gone. Born sinful or with original sin, or with a sin nature? Gone. Therefore, the need for a savior to be sacrificed? Gone. And a lot of people would agree. Good riddance.
But, it's all replaced by new teachings about how things really are.... according to the Baha'i Faith. The old stuff from the old religions is changed. Isn't it? As Vinayaka says.... "Double-speak". Baha'is believe and don't believe the old religions at the same time,