changing the name on the apple trackpad (update: 2024)
I have a magic trackpad Model A1535 that I bought used. Other answers here do not seem to work with my M2 Pro running Sonoma.
The solution for me was in this MacRumors post that describes how to factory-reset the trackpad.
In short: turn the trackpad off, then on, 5 times in order to do a factory reset.
Once I turned it on the last time, it connected, and right-clicking on the device name in Bluetooth Settings provided a Rename option that worked.
MacBook Pro 16″, macOS 14.5