Necro the death material topic? Why not
Once again, lava material is meant to form pools and flat waterfalls... any other shape gets totally borked, also visually. But for a flat lava surface, the "feet" collision detection is exactly the expected behavior. If the trigger point was near the player's center of mass, you could wade through lava >_<
Death material may be a bit strange when creating maps, but everyone got used to it. And it is purely a problem of map design if the visual clues on the map do not fit with the actual death zones and save spots that result from your placement of death material. And no, it is not that easy to adapt this to a new collision rule for all official maps. And it is still nice not to break older custom maps.