Because of how flexible and concise subscripting is, it is extremely well-purposed for creating DSLs (Domain Specific Languages).
Mattt shows a few examples and concludes with this:
This is, of course, dangerous thinking. Subscripting isn’t your new bicycle. It isn’t a giant hammer. Hell, it isn’t even a giant screwdriver! If there is one thing Object Subscripting DSLs are, it’s trouble. Here be dragons.