If you grade skill required on a one to ten scale over every facet of aviation, IMO a GA piston twin operating on one engine close to the ground and at low airspeed; is a 10.
There is absolutely no margin for less than perfect aircraft control, and in the case of an EFATO, you must do all the vital actions in the correct order and very very quickly if you are going to live.
My personal observation is that of the half dozen or so private light twin owners I know personally, only one makes the required efforts to retain the necessary skills to safely handle a real world engine failure in his light twin.
Since I know nothing of this accident pilots history I do not want to imply that this was the case here, my comment was made as a general statement.