Thread:VisualEditor/Feedback/bug 49904 not on roadmap/reply (3)

Because VE is not wikitext and subst is an extreme form of wikitext. If there is something you need, then the developers want to understand why you need it. In certain cases, an alternative solution might be sought.

For instance, I can imagine that in this case that they would reimplement some of the annotations for templates, or even for subst itself, to make sure that something like this just happens automatically. In other cases, perhaps an editor is just looking for 'action favorites' or something which. They are not trying to reimplement wikitext, they are building an editor that supports what you need to do and that is backwards compatible with wikitext syntax.

Looking specifically at PROD, it indeed seems to be implemented as a templated action for a set of templates, that insert current information (and thus need to be replaced).