The Drupal community has been on an interesting journey since the launch of Drupal 8 in 2015. In the past three years, as the community has started to get its sea legs 'off the island' (using tools, libraries, and techniques used widely in the general PHP community), there have been growing pains.
One area where the pains have been (and sometimes still are) highly visible is in how Drupal and Composer work together. I've written posts like Composer and Drupal are still strange bedfellows in the past, and while in some ways that's still the case, we as a community are getting closer and closer to a nirvana with modern Drupal site building and project management.
For example, in preparing a hands-on portion of my and Matthew Grasmick's upcoming DrupalCon Nashville lab session on Composer and Drupal, I found that we're already to the point where you can go from literally zero to a fully functional and complete Drupal site codebase—along with a functional local development environment—in about 10 or 15 minutes: