I'm going to call my date short
Is there a reason why you feel the need to point this out?
No, I'm just going to make my date unhappy about their height.
They cannot help that they are short. You should not make them feel bad about things that they cannot control.
Then short people should stop whining about it.
Being short like other things is not something that people can change about themselves so attacking them about something that is out of their control is mean. You would not like it if people did that to you for something you have no control of.