Actually higher rep deads 10's-12's-15's-20's, have been around for sometime and are perhaps more old school (see Peary Rader or Dr Ken stuff) do build your body, just like higher rep squats do.
While it is true that they are not for everyone and you have to let the ego at the door as you creep the weight up real slow over time, (same with singles) so as to not just throw caution to the wind and let the form change or loosen up the back, but they can work to build lots of power, work ethic, work capacity and mass (if adding food) over the entire body. One is most likely going to get carryover to heavier weight and lower reps from that kind of work too.
Probably guys more suited to the deadlifting (taller and longer legged) might benefit more from say a higher rep "trap bar" or PGDL (parallel grip deadlift) workout than say squats. But doing them, even if for a short stint, can be humbling.