How to set different ringer volumes for AirPods and iPhone speakers?

I like to keep the phone's ringer volume -- the one that plays through the phone's speakers -- at a high level.

Unfortunately, this means that when I am using AirPods, the call ringer and text notification are deafeningly loud.

So loud that I jump (from surprise) when they ring.

Is there a way to decouple these settings?

Specifically, I would like to keep the phone-speaker ringer very loud, but have the ringer volume when played through AirPods be quieter.

[Re-Titled by Moderator]

Original Title: AirPod-specific Ringer Volume?