You need both learning and doing

Great developers spend much of their time writing code. It's not only about how much they study, read, and keep up with the latest trends but how much time they dedicate to hone their craft. They constantly make things. Again and again.

Great developers spend much of their time reading to improve what they already know. It's not only about writing code day in and day out, but about keeping up with what's new to stay relevant. They continually augment their knowledge.

I've seen people that can't make anything useful, but they are always on top of what's new. I've seen people stuck in the past, but are excellent building things with what they know. They both have a place. They are both in the middle of the pack.

To be a great developer, you need as much learning as doing. Every day is another opportunity for you to aim higher.