Why can't Urgod/Galio etc. jump over walls w/ their dashes?

I don't main or really play the two champs mentioned.but i was curious as to why their dashes were relegated so far in terms of versatility as a result of this interaction. Especially with the rise of over tuned (personal opinion) kits with game breaking interactions like true invisibility and crazy near- unpunishable dmg (these problems are getting fixed but they still exist) , it just doest feel fair. Thoughts? Comments? Complaints?