I think the concept has value, but I think targeting today's LLMs like this is short sighted.

It's making what is likely to be a permanent change to fix a temporary problem.

I think the thing that would have value in the long term is an option to be concise, accurate, and unambiguous.

This isn't something that should be considered to be only for LLMs. Sometimes humans want readability to understand something quickly adding context helps a great deal here, but sometimes accuracy and unambiguity are paramount (like when doing an audit) if dealing with a batch of similar things, the same repeated context adds nothing and limits how much you can see at once.

So there can be a benefit when a human can request output like this for them to read directly. On top of this is the broad range of of output processing tools that we have (some people still awk).

So yes, this is needed, but LLMs will probably not need this in a few years. The other uses will remain