Superman has been played by multiple actors expanding decades, most of them have long since passed away. Yet WB don't seem to have any issues casting more actors for the Superman role.

T'Challa has been played by one actor yet when he passed away the character's just off limits. How's this make any sense? Hell how's this even fair to black actors who wanna play T'Challa?

Now what if Tom Holland (the current Spider-Man actor) pass away unexpectedly? Does it mean nobody can't play Peter Parker/Spider-Man anymore?