They did it so the 18s will sump from the get go, then they can say its normal to sump and look away from the problem.
Not all M8's sump. Put 20,526 trouble free miles on my 17 CVO Street Glide, my friend put 25,xxx miles on his 17 CVO street glide. Both were Sept 17 production date bikes.
My 18 CVO RG has 4468 miles on it, a August build date, trouble free so far. My friends 18 CVO Street Glide has similar trouble free miles.