You're thinking too concretely. The point of this article isn't to talk specifically about modeling recipes; it's to use the complexity of recipes (something concrete most people know about) as an example of how this "edge case poisoning" affects the system. I'm sure he has specific non-recipe examples in mind, but using those would either have to 1) give you a lot of background knowledge about the system, which wasn't his point 2) possibly reveal privileged information about clients and so on.
So here's a concrete example: the config file / structure for a virtual machine. Your basic VM has a # of cpus, an amount of memory, a virtual disk, and a virtual network card. Oh, but this VM is actually a "service VM" that is providing an emulated device for another VM. And this VM is actually a fast, ephemeral clone of another VM: it has copy-on-write memory and isn't allowed to write to the disk. And this VM is a live-snapshoting clone of a remote VM: it doesn't execute, but just receives memory and disk updates from the remote VM, until the heartbeat is lost, and then continues. Oh, and this VM's disk is actually provided over the network by a SAN. Oh, and...
The result being that if, like 95% of people, you just want to make a plain VM, you have to wade through a massive list of who-knows-what options to make it work. Balancing making it simple for those 95%, while functional for the other 5%, is a challenge.
But to the GP’s point, this VM config is a program, so why are you expressing it as a static config file? The ending virtual machine will be valid as long as the steps involved in its creation are.
No, it’s not, and writing VM configuration as a Turing-complete program means you can’t perform structured queries over all the VMs you manage without executing arbitrary code, and you can’t make bulk modification at all.
At least, not without restricting yourself to a tractable subset like dependabot does.
So here's a concrete example: the config file / structure for a virtual machine. Your basic VM has a # of cpus, an amount of memory, a virtual disk, and a virtual network card. Oh, but this VM is actually a "service VM" that is providing an emulated device for another VM. And this VM is actually a fast, ephemeral clone of another VM: it has copy-on-write memory and isn't allowed to write to the disk. And this VM is a live-snapshoting clone of a remote VM: it doesn't execute, but just receives memory and disk updates from the remote VM, until the heartbeat is lost, and then continues. Oh, and this VM's disk is actually provided over the network by a SAN. Oh, and...
The result being that if, like 95% of people, you just want to make a plain VM, you have to wade through a massive list of who-knows-what options to make it work. Balancing making it simple for those 95%, while functional for the other 5%, is a challenge.