User A and User B Accessed a work object at the same time that has optimistic locking turned on.

The background reasoning given for optimistic blocking is that user B  should be able to view the data on the work object while user A is actively updating the work object.

Lets say user A has submitted his version at 8 AM. Then user B who has been working on the same case (but may be different parts of the case), hits the submit button at 8:20 AM.

User B gets a warning message saying she/he has stale data and needs to refresh to fetch the latest data from the DB. 

And when user B clicks on the "refresh" button on the warning message: ALL of the updates that user B made on this WO are now gone! because the clipboard is now refreshed with user A's version of the WO.

What is the point of optimistic locking anymore? Pega has always had the capability to build readonly harnesses  from many versions earlier.

Can anyone help me understand how this user experience of losing all your updates as user B did above is at all worthwhile? How is optimistic locking helping any one in the real world?