I still believe that my #1 think that stunted my growth as a junior SWE was overthinking my personal projects and languages to use for them, instead of just building whatever I felt it's interesting or intriguing to build.
To me it sounds like you learned a real important lesson one that some people never seem to learn.
I think one of the most beneficial aspects of doing things "just because" is these other skills or information you get along the way. It is very easy to miss all of this progress if you're too focused on the progress of the more tangible things. But that doesn't make any of that not progress. So don't put yourself down for that, because I'm sure you learned a lot. The only reason you can look back and see a better way is because you made that progress and learned those lessons. These are things mentors can usually help you get through faster but not everyone has a mentor nor access to one. But don't undermine your own progress just because you didn't finish projects or because you did things differently than others
other people use the stupidest possible javascript to launch product and really focus on product and marketing
yet other people stay as far away from computers as possible and focus on more human activities
you just do what you're drawn to naturally