[2019] I don't understand the anti-camping measure which is the boss lair sounds

My understanding is that there is intended to be a sound which begins at approximately 80m from the boss lair, a demonic whispering, which happens to all players so long as the boss is alive. At 40m it will get louder and more intense. If the boss is killed, it goes away. The absence of the sound is intended to alert incoming players that the boss has been killed.

My confusion is, there is already a sound made by the boss when it's alive. The butcher stomps. The spider scuttles and screaches. The Assasin growls and whooshes. The only difference is the distance. So how does this change anything?

Am I missing some aspect of this new mechanic that means it makes more sense? Or is it literally just extending the distance from the boss lair that you can tell there is a boss?

edit: I found this video of Dennis explaining it to Psychoghost in a recent stream: https://clips.twitch.tv/GrotesqueAmazonianGrassVoteNay

Here's what I think I missed.

at 80m, there are two intensities of sound. The more intense sound indicates other players are inside. The less intense sound means the boss is alive and you're the only one(s) there.

at 40m, the sound is intense and you cannot tell the difference between if there are other players there or not.