As a regular human, he'd only have to worry about things like homework or tennis practice, much as Connie does. Sure, Connie thinks that learning sword fighting is fun (which I'm sure it is), but she can quit any time she wants. She always has a way out. She can go back home every day and live a normal human life. Steven, on the other hand, frequently has to worry about keeping himself and his friends from dying, attacks on his own home, and repercussions from a war he didn't even fight in.
Steven does think all that stuff is cool, but he never gets a break. He never knows if Garnet, Amethyst, and Pearl are all going to return from the next mission. He sometimes has to comfort the gems, who are supposed to be parental figures and a role models. As a kid.
I think the most interesting part of this theory is how the series could end. Now, we know if Steven gets poofed, he'll be dead forever. However, what if there was a way for Steven to separate from his gem? What if Steven can become fully human, without needing his gem, thus allowing Rose Quartz to return, without Steven ever dying? We'd probably all like for Steven and Rose to meet somehow, so wouldn't it be amazing if that was Rebecca's plan all along?
Check out the video below for the full theory, and discuss below about Steven's humanity!
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