I want to tell my short coworker to get a step stool for something they couldn't reach, even though I could
Why not just help them reach it?
I don't like short people, and I like to make them uncomfortable
It's wrong for you to judge people based on their height, because they have no control over the way they were born. When someone has difficulty in the workplace, you should be willing to help them, especially when it would be so easy for you to do so.
Sorry that's not how I was raised.
All you have to do is grab the item for them. You should help your coworkers if you see them struggling to reach something.