What's the likelihood of irrecoverable civilizational collapse if 90% of the population dies?

Having estimates of irrecoverable civilizational collapse is extremely important because it determines whether nuclear risks and pandemics are X-risks or non-existential global catastrophic risks. So I'd love to have people's thoughts on this, especially from people who have thought about it. It doesn't matter if it's a rough estimate. 
 

The only investigation I know of is Luisa Rodriguez's one and my understanding was that she didn't put a lot of weight on it but it seems like it's an argument that seems important in other thinker's worldviews (e.g Toby Ord mentioned this in a private discussion to explain the high probability he gives to biorisks being an X-risk) so I'd like to get a better sense on people's view on that question: 

What's the likelihood of irrecoverable civilizational collapse if 90% of the human population dies?