Why reusable workflow option of internal repo is only available in the enterprise cloud edition ? Why not in normal edition?

Internal repo option is not available in this https://docs.github.com/en/actions/using-workflows/reusing-workflows#limitations

But accessing the internal repo option is available in this https://docs.github.com/en/enterprise-cloud@latest/actions/using-workflows/reusing-workflows

Is there any alternate solution for accessing the private repo from internal repo? or else when will this solution will be made in GA?