The content of Black Label is in the form of Classic Editor text (for simple pages) or Gutenberg blocks.
You can install and use other page builders but we recommend that you do not install and use them as they are likely to become deprecated in the future.
Furthermore, they are maintained by fewer developers and they may contain security issues.
Gutenberg is a long-term solution with solid and secure code. It is maintained by WordPress core developers and has new improvements and blocks coming frequently.