Yes, the Holden Commodore is indeed underrated considering they discountinued just a few years ago.
They were great cars and popular cars back in the day. The ZB Commodores weren't that great as they weren't even built in Australia. The VF Series II Commodore were the best modern Commodores, although the VE and VT Commodores were also great cars.
The VT were great cars and their main competitor they easily beat anyway because their competitor was the AU Falcon