Good topic, @Avery - it's definitely something that is under-referenced.
In fact, to go beyond the scope of the article a bit, it's not just for graphics (although that's the usage that requires any editing outside of RPG Maker). Using placeholders is a good technique for anything that's holding up your project.
Not sure how to balance your enemies' and classes' parameters? Make them whatever until the maps and story of your game are finished.
Not great at mapping, or not sure what details you might need? Make simple maps for each place until you've created all of the locations you'll need to finish your game.
Don't have the dialogue for this NPC written out fully? Just talk to them and advance your story trackers for now.
It's easier to fill in details and specifics once you have a framework constructed.
You are right, this also applies for many other aspects of game making. Plus, it saves you from investing time (maybe the one of other people, but that does not really make it better xD) on things that might ultimately be scrapped when you realize you need to remodel that part of your game again.
If you have a wonky looking prototype with gaps that works you can start sorting out what stays and what has to be changed and save yourself a lot of fuzz (though I fully understand that that is not the perfect workflow for everyone).
@ATT_Turan I often when I was streaming put in just very basic dialogue that covered the bare bones of what the scene needed to communcate and just said "yep, that is getting rewritten later" and moved on.