Changing an interaction type to Active Engagement will not retroactively update any records that have already added activities using these types. It will only take effect on new activities added after the change. Allowing users to select, when updating these if they would like for the existing activity types to be updated would allow them to have a better view of when their team have been reaching out to their customer
I think this would be very difficult to implement. And it would be impossible to do the opposite (undo active engagement if the option is deselected) so I think this is unlikely to be implemented.