OpenOCD needs that the Atmel-ICE is loaded with libusb drivers in order to be able to access it. Similiar as per Setting up Atmel-ICE with PlatformIO using ATmega328p – Cyan Sensors and How to setup Atmel-ICE to program an ATmega328 on PlatformIO with VSCode on Windows 10 - #13 by jcsb1994.