I think the ‘helpful’ part of this depends where on the curve you sit. If you feel like you’ve been taking your training seriously for a while (not a beginner, made adjustments to your diet, think about recovery and in general improvement focussed) and then you find yourself left of where you think you should be, I could see that as potentially demotivating.
The flip side of this of course is some kind of enlightenment. My wife is a good example. She doesn’t see herself as athletic, yet has completed 1/2 marathon events and has been a swimmer for years. She has zero interest in bikes or bike riding but once I got my pain cave set up I suggested that she give it a go. An efficient and convenient way to get some exercise in since it’s in our garage. She does not in any way identify with being a cyclist and generally lacks confidence about anything bikes. For her cycling is sitting on the bike and making her legs go around as some kind of Coach Chad marionette. She thinks she’s slow and the fact that my FTP is almost 3X hers doesn’t help her ego (I’m a LOT heavier though 
). When I showed her that in fact after only a few months of TR workouts combined with her existing fitness, she is already right in the middle of the bell curve for TR athletes in her age group, she was really surprised. I don’t think it made her any more interested in being a ‘real cyclist’, but it gave her some legitimacy and corresponding confidence that wasn’t there before. Baby steps!