I know of so many people that have improved using TrainerRoad and I wish more of my cycling friends would use it rather than complaining they aren’t improving.
I think a lot of them would need to feel that someone is monitoring their data to trust a training plan and would probably need to be told that their training is sufficient and that they don’t need to do more.
I imagine they would also benefit from talking through their reasoning with someone and figure out why it doesn’t fit with trainer road and so that any false beliefs they might have could at least be made apparent if not challenged.
The hardest part to progressing seems to be trusting and committing to following a plan. The plan itself is just details.
Have you thought of offering ‘accompanied’ TrainerRoad plans? With regular catch-ups / oversight from a physical person?