Take another look. What you get now is still a gigantic JSON file... except it opens in a two-pane window, with the default settings (including detailed documentation in comments) on the left, and your local copy on the right. And beside each setting on the left is an icon where, if you press it, it copies the setting into your local copy, with all the correct JSON syntax. And usually there's a dropdown showing the different valid options and it uses folding to divide neatly up into sections. Oh, and the settings instantly apply when you save the file.

To me, this combines the best parts of being a text file --- standard commands, formatting the way you like it, you can search it, version controllable --- with the best parts of a GUI --- prompting as to what options are available, easy selection of alternates, documentation, etc. It's an amazingly good implementation and I wish more applications used it.

(e.g. the comment for editor.lineNumbers now tells me that valid options are 'on', 'off' and 'relative', which counts relative to the line the cursor is on.)