Family sharing vs Apple One

"If you have the Apple One Family or Premier plan, you can use Family Sharing to share all included Apple services with up to five other family members. And Apple TV+ and Apple Arcade always include Family Sharing, even in the Apple One Individual plan."

(you) + (five other) = 06

One allows 6 people. The Organizer and 5 other people. Total of 6.

As Siabh points out, the organizer is referred to as “you” and the 5 other people are in addition to you. You + 5 other people = 6 total people.

This is pretty much what is available on Apple One at this time : https://www.apple.com/apple-one/