There were 3 people involved in the transaction.
Hopefully that makes it clearer. It's the yellow outputs that have been anonymised by this transaction, not the inputs or the change outputs.
In that particular example, wouldn't it be more anonymous to just have 6 outputs of 61.04976087 BTC? (That's the total amount less tx fees divided by 6, or 3 yellows and 3 change outputs of all exactly the same amount).
That way, even the "change" outputs can no longer be tied to the three people.
Sure, it's possible. With a lot of coinjoin services, you can split the amount over several addresses. This is encouraged by some of them, and it should theoretically be better for privacy.