If saving faith in Christ is a God-given gift, what prevents God from giving this gift to everyone?

If saving faith in Christ is considered a gift from God rather than an attainable skill through personal effort (as discussed in *https://christianity.stackexchange.com/q/99625/61679*) , then what prevents God from bestowing this gift universally? Why doesn't everyone on the planet just wake up the next morning with the God-given faith that Jesus is their personal savior? Are there unstated conditions preventing God from doing this? On the other hand, if God does offer the gift of saving faith to everyone, then why does it appear to be case that not everyone receives it? Why is it the case then that so many people around the world fail to proclaim to have saving faith in Christ (including adherents of other religions, atheists, agnostics, etc.)? Why would anyone in their right mind refuse such a powerful, life-changing divine gift? I'm seeking an overview of perspectives on this matter.