https://en.wikipedia.org/wiki/Bus_factor is a thing that any GOOD project or IT department considers. How many of your staff can you afford to lose if they all happen to be travelling in the same bus, on their way to eat at the same place for lunch when an asteroid inevitably punches through said bus and/or diner.
'Hit by an asteroid' is a little unrealistic. Sentenced to prison for 15 to Life has happened in the Open Source community at least once before. The project I linked to had a Bus Factor of about one. It's now 'old code using outdated APIs' and is considered obsolete.
I've personally seen legal and criminal issues for a single individual cripple IT departments before, meaning their bus factor was also way too low. I've been on trips that have been rudely interrupted by screaming executives when I came down out of the mountains into cell range because I was the only bus factor left on certain systems. Natural disaster, such as hurricanes, wildfires, and floods are very serious existential threats to even the largest of organizations.
Since Linux seems to be a good project, I can't imagine that the discussion hasn't been had, in public or in private. Millions of individuals and dozens upon dozens of big corporations depend on Linux, Open source and otherwise. If the bus comes for core maintainers or project leaders we have at least SOME backup.