To be fair to Planet X they source from suppliers who make frames and forks for a lot of brands.
But yeah, inspect stuff from time to time. The topic came up on STW and there's people saying essentially 'anything can break' and it reminded me that in the summer I found a 2″ crack on the bend of an Al bar that I’d had on a gravel bike for 3-4 years. Sweat corrosion under the tape ate into the surface and started a crack. That would have been a fairly dramatic moment when the crack grew to a total failure as it was hidden under the tape. That's what I like about metal kit, if you look for the signs it gives a warning before it fails.
I feel that this kind of incident is one of those ones that is so without warning and also so statistically unlikely that it can't be mitigated against other than by not riding a bike.
A serious crash and outcome might come from something else like a blown out tyre or a stem face plate going, I agree. Still, imho carbon forks might raise your risk over a steel fork if that's an alternative, by how much is hard to say. My experience of cracking or raking out a few steel forks says I trust them to remain rideable even when they're past the point of no return. It's about how things fail. And in all this I do have a bias (from experience at least..), I really like steel as a material and I think carbon is horrible stuff, so what I say should be read with that in mind : )