This is definitely a good approach but I don't think it's the only one!

I absolutely agree that the idea that exercise has to be unpleasant is wrong and harmful. But there's a middle ground where the things you actively enjoy aren't sufficient to keep you fit, and so you develop a habit of doing regular exercise even when you don't feel like it and even if it's a bit boring and effortful.

Everyone's different but IME this works well provided you build up the effort level gradually, and never feel the need to push yourself to a really unpleasant degree. Eventually habit, the knowledge that it's good for you in the long run, and the fact that it usually makes you feel better in the short run make it pretty easy to stick with.