The answer is connection.
Humans naturally attach memories to sound.
A familiar melody can trigger memories more quickly than a photograph. A particular vocal performance can bring back an entire period of someone's life within seconds.
That is why hearing an old song after many years can be almost overwhelming.
Suddenly, a person remembers where they were.
They remember who they were with.
They remember what they hoped for.
They remember what they feared.
They remember the person they used to be.
When the singer behind that music dies, listeners may feel as though the world has closed a door on that period of their lives.
The singer's death becomes a reminder that time has passed.
And that realization can be surprisingly powerful.
The End of an Era
When a major musical figure dies, the reaction is often described as the end of an era.
That phrase can sound exaggerated, but sometimes it is accurate.