Why doesn't the radio work in my 2016 Isuzu D-Max?

Blowing a major fuse suggests that your car has suffered a short-circuit somewhere within its kilometres of wiring. But a modern vehicle like your Isuzu will also have fuses protecting the various systems it needs to operate, so there’s a chance there’s a second fuse that protects the stereo system that has also blown when the problem occurred. Your owner’s manual should be able to identify the locations of the car’s various fuses. Don’t forget to replace them with a fuse of the correct amperage or you could cause more damage if the fuse ever needs to act as a circuit-breaker again (which is exactly the fuse’s role).

The other possibility is that the stereo unit itself has an internal fuse. Check around the rear of the unit (usually where the wiring for the speakers exits the stereo) and you might be able to locate the fuse in question. This is often the case in aftermarket stereo systems.