I don’t use Elementor or BB, but I use other plugins, and I’m sure we all have plugins that we are attached to. A possibility may be to support ClassicPress v1 as an LTS that will always be compatible with WP. As in, regardless of whether the plugins officially support, they should always work. Sort of like Drupal 7 is still in wide use, even though the latest is Drupal 8.
The less complicated plugins can be forked and adapted by us or the ones supporting CP will move forward into further versions as well.
I think if we plan features on further versions of CP that are desirable but absent on WP, it will be motivation for plugin developers to intentionally support.
For example, properly supporting plugging more customizations into tag and category pages as well. SEO related optimizations, featured images, custom fields to support linked data making the site way more accessible to AIs… Instead of all the semantic plugins doing half baked jobs of linked data or very expensive paid alternatives, linked data could be a reality with existing tags and categories. BOOM. No more having to recreate endless terms and so on. Can’t imagine any future conscious developer not wanting to support that.