Why did god allow people to be born after the fall ?

[John V]

Not so.  Taking Descartes at his word, the presence of thoughts would cause you to exist. 

They're not your thoughts - they're God's. Only God exists.

You'd essentially be your god's puppet

And people can do as they please with a puppet; or writers can do as they please with a character. Regardless of the treatment of such, it's not moral or immoral, it's amoral.

By forcing us into one afterlife place or another according to its will, and by forcing many people to say words they don't actually believe, out of fear.

Telling us about reward and punishment influences our behavior, but it doesn't constrain it. If an all powerful God were constraining our behavior, we'd all necessarily be obeying.

I could drop down on my knees right this instant and blurt out the Sinner's Prayer, but I won't.  Know why?  Because I don't believe it and in fact have never believed it.  I would be lying to myself and lying to your god, and to me it just isn't worth it.

So, if god exists, that's proof he's not constraining our behavior.