Is OJS software in any way based on the Drupal framework?
OJS uses Smarty framework.
I think it would be more accurate to say that OJS uses a proprietary framework which leverages several standard components, such as Smarty templating.
Perhaps we can see a standard framework for the 4.x release!
I arrive two years late to the conversation but, even more accurate…
Drupal is a generalist CMS-framework build with PHP (and using smarty as a template system).
Drupal 8 moved from his own framework/api to Symfony (with twig as a template system).
OJS is also a CMS but is not generalist, it’s focused in journal publications.
OJS is build with PHP over his own framework (with smarty as a template system).