It seems that you are arguing that because Healing Word restores consciousness to a PC that has been reduced to 0 hp, and Healing Word is healing magic, than the PC must have taken meat damage.
However, by this same reasoning, if I cast Healing Word on a character that has taken 2 hp of damage, healing word is still healing magic so any hit point damage is meat damage.
My point is that you don’t know if the damage is fatal until it kills you.
You’re assuming that each death save represents getting closer to death or closer to recovery. But you don’t have to make that assumption.
The game makes more sense if you assume that you don’t know whether a blow is fatal until you actually die from it. If you roll a 20 on the death save, guess the injury was less serious than it appeared. Same thing if you get healing halfway through. If you fail your death saves though, I guess the injury was more severe than it looked.
This second way of looking at things is more consistent with what the characters see as well. If I am fighting hobgoblins and the wizard goes down, my character has no way of knowing whether he just got his femoral artery severed or just got the wind knocked out of him.