In the image if you wanted to turn the character’s head to the left you point your fingers to the left.

You’re not wrapping your head around it correctly

“Up actually means down” is not what people that think with inverted Y-axis. It’s if I pull back the mouse/joystick it’s going to tilt the character’s eyes up.

Image you are flying a plane and you have a single control stick in front of you.

Which way do you move the stick to climb higher in the air?

Which way do you move the stick to turn left?