Based on MC-64261 I assume that there is some code which should prevent players, who died from seeing what's going on after their death.
When you die, you keep the chunks loaded.
How to reproduce:
- /tp ~10000 ~ ~ (in a area which isn't loaded by default)
- Place a simple redstone clock with a command block containing a command, for example: /say Loaded
You will see that the command block continues printing "Loaded" until you press "Respawn".
In general there is no reason why a dead player should be able to see what is going on after their death, so you could even consider this as an exploit. A solution would be to stop sending a dead player any player, entity or chunk updates until he respawns.
If someone wants a dead player to be able to spectate, they should use the spectator mode I guess.