Ed Sheeran just plays the standard pop chord lineup when he plays guitar. E, G, C, A, D. The rest of the guitar is wasted space in his hands. It’s definitely a joke about a musician specifically for musicians to laugh at.

His music is childishly simple and uses pretty much a singular method of music theory and the circle of fifths and caters wholly to the major scale. He writes baby music to be played on a baby guitar.

I'm guessing Ed Sheeran has no neck? Lol

He's small. That's it.