I've made a copy of your action area field and configured the conditional for you. I've confirmed it's working as you were wanting. Please also confirm and review the condition carefully.

1) What does the 1 in the value denote ?

It's an IF substitution ensuring the viewing user is never the profile owner.

2) how can i add the Tabs to this value (like files and contact info) to replicate this behavior for them too ?

You can't condition off the visibility of a tab since a tab output is never actually empty. I mean you can try using the below condition, but I doubt it'll work.

Display: Field conditional self
Field: Custom > Value
Value: [cb:usertab tab="TAB_ID" /]
Translate Value: No
Operator: Is Equal To
Value: (leave empty)
Translate Value: No
Mode: Show

The action area condition has 2 substitutions in it. First an IF substitution to check if the viewing user is the displayed user and if they are it outputs a 1 to the value. Next it substitutes in the HTML display of the avatar field and it does this because CB Privacy specifically nulls this view. So what this means is if the field is hidden by privacy and the viewing user is not the profile owner the condition will compare 2 empty values and pass.

You can not condition a field multiple times. There is no AND or OR conditional usage yet so they all act independently of one another.

There are also no IF substitutions for tab content. The substitution IF usages use raw data values so they won't be able to work in your scenario since CB Privacy does not suppress raw data and only suppresses HTML output of fields.