[doublerabbit]

Nothing is a point of failure if you can switch but that's not really true unless you have fail-over.

If LE was to go nope right now, how fast could you move your stack from LE?

You can't use multiple SSL certificates as redundancy. You could probably create something bespoke with a Load Balancer and SSL offloading but that's just more overhead for really nothing.

[po1nt]

Just picture the massive load spikes on other SSL providers in that moment. And the fact that even those might not work, as their backends might rely on LE SSL 3rd party services for ID checking or something.