Bricking has never had a solid definition. The most useful definition is a product is bricked when the owner does not have the skills/time/money required to get the product in a working state. The product is a brick to them.

If you flash bad firmware on a device and overwrite the bootloader used for flashing, many would consider this a bricked device since they don't know how to use an SPI flasher to restore a working firmware. For others simply having a device that isnt fixable via a factory reset is bricked because they don't know how to flash via usb.

A car that has become software locked without a way to restore it is bricked imo.