My Powerbeats Pro is auto connecting with my MacBook Pro

Welcome to the Apple iCloud ecosystem! The issue you're experiencing stems from Apple's iCloud syncing feature for devices in the Apple ecosystem. Bluetooth devices like your Powerbeats Pro are linked to your Apple Account, allowing them to seamlessly switch between Apple devices. Convenient, but not always desirable.

However, there are some options you can take to minimize this "behavior" ... but, none of them are ideal. The bottom line? Get into the habit of disconnecting devices, not forgetting them.

Option #1 - Disable iCloud Syncing for your Bluetooth Devices

• Unfortunately, Apple doesn't allow you to disable Bluetooth device syncing across devices directly. However, you can work around this: Pair your Powerbeats Pro (or other Bluetooth devices) with only the device you want to use. Unfortunately, when you "forget" a device, it syncs that action across iCloud.
• So, instead of forgetting the device, turn off Bluetooth on devices you don't want the Powerbeats to connect to when using them. Alternatively, disconnect the Powerbeats from the unwanted device instead of forgetting it.

Option #2 - Use Separate Apple Accounts for Devices

• I am not recommending this one, but if you're willing to separate your Apple Account usage (e.g., one for your iPhone and another for your MacBook). Keep in mind, this also disables other iCloud features. Again, not recommended, but it is the only sure-fire way to stop this behavior.

Option #3 - Manually Manage Bluetooth Devices on macOS:

• On your MacBook, you can prevent automatic connection without forgetting the device: Go to System Settings > Bluetooth. Locate your Powerbeats Pro, then click the (i) icon. Choose "When last connected to the Mac" under "Connect to this Mac." This should ensure the MacBook won’t actively pair with the device unless you manually reconnect it.
• Unfortunately, there is nothing like this with iOS.

Option #4 Finally Consider Using a Third-Party App for Bluetooth Management

• One that comes to mind is ToothFairy.

Yes, if you paired your Chevy to your iPhone to use something like CarPlay, then it became part of the Apple iCloud ecosystem. That's why you would see it on your Mac. That's how it works. Not sure how this exposes your Mac to any Bluetooth device. By default, any Bluetooth device within range (~30-40') will show up as available devices. That, in itself, does not pair it. That would require manual intervention.

For example when I got my new car recently, the dealer walked me through pairing my iPhone with the vehicle's CarPlay system. The phone, nor the car, initiated this process automatically. Instead, it was done manually, where one the process was started, the car sent a code to the phone which you had to verify matched. One done, the pairing process completed.

Crs0zero wrote:

This is a serious matter and will likely affect my future decisions about buying apple products.

Even if this were a security issue, Apple products remain more secure than those of most other manufacturers. Do your research carefully so that you don't end up avoiding one minor risk for a whole lot of bigger ones.

The BT on iPhones is locked down much tighter than on Android phones. Apple has intentionally not included the file transfer capability.