The way the blast works is: the closer you are to the explosion the more damage it does, so technically yes it has slight damage fall off, this also means crouching and hitting a player's feet will do more damage than if you hit them at their head.
@@adhirmanandhar1942 it's literally impossible because the maximum possible damage is quite below the Medic's 150 health. Unless your example goes before 2015.
@@capofantasma97 or he got oneshot because of the shield bash, or maybe he got hit with the minicrit of the shield's charge, assuming the demoman used a shield