I think whatever learning method depends on your goals, are you trying to get immediate deep experience that a general (still quick-feedback) but intense brushover of all the fundamentals can not provide, then project-based learning is good for you, but if you're looking to not only master the fundamentals but also advance in terms of being able to offer more on the fundamentals, then traditional course-based learning is good for you.

I don't think there is a real good or bad but rather depends on your goal and motivations. Depending on the goal, some people might learn more from projects than course content and vice versa.