Drupal is certainly not only the open-source CMS game in town, but when consulting with clients about the best solution for the full range of their needs, it tends to be my go-to.

Here’s why: 

Architecture
Scalability
Database Views
Flexibility
Security
Modules
Search
Migration  
Architecture

Drupal 8 is built on modern programming practices, and of course, the same will be true for June 2020 release of Drupal 9.