It’s technically correct but really we all know what was meant. They’re serialisable but not really deserialisable, even if it’s a pure function it might not even be serialised in a version of JS that the receiver understands.
> serialised in a version of JS that the receiver understands
I don't think the use case for this is as general as most RPC systems.
The linked site envisions a situation where you had an app running on one server, now you want to break that workload up while making the absolute minimum number of code changes.
All the clients and code would still be controlled by the same team.
that's still not something I'd want to inflict to myself. That means you need to somehow ensure the functions you pass are pure, and that upgrading Node or changing the compilation target could break the app if the release rollout is progressive.
Using function serialisation for applicative purposes is always going to be a hack that will come back to bite the team at one time or another.