The fundamental point is what you're getting paid to do. Is the company paying for your experience or aptitude? If it's the latter, becoming a better programme

The fundamental point is what you're getting paid to do. Is the company paying for your experience or aptitude? If it's the latter, becoming a better programmer is part of your job, and choosing to read books instead of writing code is just a choice of priority, just like choosing to work on one feature of the project over another. If it's the former, ask yourself if you really want to be working for this company.