Hi juniperjoe,
Apple does support pairing to multiple devices at once, but it does it using a specialized chip and your Apple ID. If your two devices you're trying to quickly swap between have different Apple ID's that feature won't work.
"Switch automatically
AirPods are connected to your iPhone and Apple Watch at the same time. Sound switches between them automatically.
To switch between devices automatically with your AirPods (2nd or 3rd generation), AirPods Pro (1st or 2nd generation), or AirPods Max:
If you're signed in with the same Apple ID on your devices, your AirPods will switch automatically from listening to music on your iPad to answering a phone call on your iPhone, for example.
In some situations with macOS Big Sur or later, you'll see a notification about your AirPods on the screen of your Mac. Click Connect to confirm that you want your AirPods to switch to your Mac or stay with your Mac."
You can still toggle Bluetooth off on one device, and press and hold the button on the back of the AirPods case until the light on the front blinks white to put it into pairing mode to then connect it to your different device.
If you'd like to see additional tweaks to how AirPods handle multiple devices or automatic switching, we'd advise leaving feedback for Apple here:
Cheers!