The main selling point of October is that it is based on Laravel/symfony. For PHP developers who are already familiar with Laravel/symfony, that is a big advantage over other box software. I understand that Drupal began using symfony with v8 as well. The Drupal team also clearly sees the advantage of using existing, time-tested, and robust technologies.
Yes absolutely understandable! Although, if I look at the "Projects using Symfony" website, it seems most popular CMS systems are using at least the components (https://symfony.com/projects)...