There are calls in the Drupal community to provide long term support for Drupal 7. Some folks in the Backdrop CMS community believe that in a way, Backdrop CMS could already be a long term option for Drupal 7 sites that are not able or willing to move to more recent versions of Drupal.

Yet, Backdrop is not a drop in replacement for Drupal 7. Moving to Backdrop requires an upgrade that is easier than moving to Drupal 9, but it is not trivial, especially for the folks with large amounts of custom code in their Drupal 7 sites.

In this discussion on 'Should Backdrop CMS be Drupal Classic?' on 16^th July 2022 questions like Is there a role for Backdrop CMS? Can or should we think about Backdrop CMS as an "unofficial" Drupal Classic? What can we still do to make the Drupal 7 to Backdrop CMS upgrade even easier? will be answered.

Source: BackDrop Events