Drupal 8 has been dropping in it's market share for two years, but not it's drop seems to be smoothing out. I expect it to stop. Drupal 8 has been more complex thatn Drupal 7, but also more powerful. It has been made from a 200hp engine into a 400hp engine. You may want a 200hp engine in your car, and then you can choose something simpler and cheaper. But then, if you will want to use it for something more powerful, you would actually need to buy a new, more powerful car, and end up paying more.