XBox “organizer” account needs to be deleted or changed

You would have to remove your sisters ex-husband from the account inorder to do this.

The organizer may need to remove the account first as a member and then re-add as an organizer? As the organizer she can not remover herself, I created another organizer who can not remove her organizer account or change it to member?

I have this same question....

I added another account to be the organizer, but now I need to change the original organizer to show as just a member.

You need to log in the accou that has the family organizer badge.
With that account you can change the privacy settings of the other accounts.

Or also remove and re-add the other accounts as family organizers

Hi and thanks for reaching Microsoft Xbox gamer's community. My name is Josef.
I'm an Independent Advisor and a Microsoft Xbox user like you.

Hope you're doing great today despite this Zenaaxx

Please note that changing the birth year doesn’t delete this restriction.
If you’re using a child account and if you’re not able to change your privacy settings here
https://account.xbox.com/Settings

You need to ask to the family organizer / join to a family group and use an adult account in order to change and enable the multiplayer features in your account