To avoid the massive utility of knowing that another intelligent species survived the great filter
It has survived it so far, but for all we know it may be going to be extinct in 200 years.
The first such civilization surviving thus far still provides a large quantity of information. In particular, it makes us think the early stages of the filter are easier, and thus causes us to update our probability of future survival downward for both civilizations. In other words, hearing about another civilization makes us think it more likely that said civilization will go extinct soon.
If it's worth saying, but not worth its own post, even in Discussion, it goes here.