Drupal underwent a dramatic redesign when moving to Version 8. Overall, the emphasis went towards enterprise-level projects and an assumption that a website would have an army of systems people behind its initiation, development, and maintenance.
The code-base increased dramatically with the incorporation of an extensive PHP framework called Symfony. The ease of creating a module went from do-able, to just-about-impossible. The difficulty of creating a module became so high that a new tool was developed (Drupal Console) just to ease the load. In an ironic twist, Drupal Console made it so easy to create the complex structures underlying Drupal 8 modules that it became so trivial to create Drupal 8 modules that there came a vast proliferation of Drupal modules of such high complexity that their own "authors" don't even understand the technology underlying them. Paradoxically, Drupal 8's module-creation difficulty has led to an overpopulation of Drupal 8 modules.
My brain doesn't accept incomprehensible complexity. I want to understand what is behind the technology and I want to know how it works and I want to manipulate it. Throwing hundreds of thousands (or more) lines of code into a big pot is not something I am comfortable with. I prefer to distill and reduce and eliminate unnecessary complexity over creating more complexity on top of a heap of other complexity.
Furthermore, I am not married to PHP. Becoming a wizard of the dark arts of PHP is not my goal in life. PHP wizards understand the subtle differences of "classes", "abstract classes", "interfaces", "traits", "late static bindings", "static methods", and "duck-typing" within the particular world of PHP. I prefer simple, straightforward programming, and prefer a more targeted use of objects and classes.
The complexity of Drupal in 8 and beyond is not limited to simply the scale of the code and the intricacies of the underlying language. Tools like Composer seem to be de rigeur in order to competently manage a higher level Drupal site. Composer has noble goals and aims and is a very useful tool. However, it is also quite complex and has its own learning curve. When you add to the Drupal learning curve also the learning curves of Symfony, Console, Composer, and dark-wizard PHP-OOP (object-oriented programming), you quite simply end up with a world that is beyond the scope of comprehension of most mere mortals.
I have had enough work to get my Drupal and Git concepts in order, to get my development environment in order, to learn the PHPstorm debugger, Xdebug, NGINX, and to manage my sites and am not interested in increasing my workload by an order of magnitude simply to reach a point of productivity with Drupal versions greater than 7.
The Drupal Organization has announced The End of Life for Drupal 7.
I say, "Drupal 7 is dead! Long live Drupal 7!"
