Blast from the past thread.
So I stuck with TrainerRoad and then bought a new mountain bike.
TrainerRoad is for cardio fitness and weight management. Mountain biking is for fun, but I am getting coaching and watching loads of YouTube tutorials as I am really enjoying learning new skills and striving to be less shit. It’s a challenge as much of what I ought to do is the opposite of what my body does instinctively. There is something fun about getting through corners without braking, finding step downs less intimidating, getting over rooty sections cleanly etc.
tl dr fun and fitness