Mixed messages? Are you sure? I have been listening to the podcast regularly for several years, and “Don’t diet on the bike!”/“Fuel your workouts.” is one of the mantras of all of the hosts. Ditto for the amount, 80-100 g of carbs seems achievable to most, although some can go higher. Cutting carbs seems very unwise to me.
For reference, an older thread on fueling popped up, and I reckon it might be of interest to you. While it focusses on fat loss, it covers the basics on fueling strategies. Other people with infinitely more expertise than I have such as @Dr_Alex_Harrison have contributed to it, too, and you might be interested in checking out what they think, too.
You can do most TR workouts, including very hard ones, fasted. But that doesn’t mean you should. IMHO not fueling on the bike means you are shortchanging yourself over time. Do you disagree with any of my reasons specifically?