Is the DMG 3/4 cover diagram in 5e incorrect?

From page 250 and 251 of the DMG:

To determine whether a target has cover against an attack or other effect on a grid, choose a corner of the attacker’s space… trace imaginary lines from that corner to every corner of any one square the target occupies. If one or two of those lines are blocked by an obstacle (including another creature), the target has half cover…

grid diagrams taken from the DMG. The final diagram shows the construction lines provided in the DMG to determine cover (showing 3/4th cover) as well as the question askers own construction lines, superimposed showing it should be half cover.

It looks like they just chose the wrong corner. If the attacker was moved one square to the north it would be 3/4 cover. Or do you think they meant "choose the closest corner"?