I personally think Laz cherry picks people he know wont succeed (i.e. worlds toughest mudders, thru hikers, and gary robbins) to race Barkleys because he wants the reputation to remain as a race that rarely has finishers.
Gary Robbins is a good runner...but an elite? no. He has won some 100s like HURT but comes in hours later in the competitive ones.
Will Laz ever invite a Kilian, Francois or Xavier? Probably not.