Tiny toss interactions

Was watching Summit 4 where Tiny tossed a wisp to death but how did Wisp, a floating ball of sentient photons, take damage when falling? He floats but he takes damage when falling?? And on that topic, how does Lina, CM and flying units like viper and wyvern take damage from toss?? IceFrog please fix in 6.86! Tiny's toss is clearly bugged!