No trailing commas is great for enforcing consistency. I’ma huge fan of consistency in code. Same with required quotation marks, which also simplify writing (imagine having to wonder if something needs it, or be surprised when it does and things break).
You've also got it backwards on quotes, it complicates writing by forcing you to write more. And with "Especially when automation exists" wondering is a non-issue, you'd get the syntax hint/error right there while typing and see if you need quotes before anything breaks
> Having to add a comma when appending to the list doesn't seem that bad to me as a trade off.
Then do that! No one is forcing you to add trailing commas, they're optional and for all the other people who don't think they add value
> Commas exist mostly to help JSON be human-readable. They have no real syntactic purpose as one could make their own notation without the commas and it'd work just fine.
https://stackoverflow.com/a/36104693
Elsewhere such commas can be optional, e.g. in clojure: https://guide.clojure.style/#opt-commas-in-map-literals
{ foo :"bar" baz :"bak" quux :[ a,b,c,d ] lol :9.7E+42 }
my-abstr x y z foo: "bar" baz: "bak" "quak" quux: [a, b, c, d] lol: 9.7E+42
my-abstr x y z, foo: "bar", baz: "bak" "quak", quux: [a, b, c, d], lol: 9.7E+42
Coloring things is a luxury, and from my understanding not many people understand that fact. When you work at the trenches you see a lot of files on a small viewport and without coloring most of the time. Being able to parse an squiggly file on a monochrome screen just by reading is a big plus for the file format in question.
As technology progresses we tend to forget where we came from and what are the fallbacks are, but we shouldn't. Not everyone is seeing the same file in a 30" 4K/8K screen with wide color gamut and HDR. Sometimes a 80x24 over some management port is all we have.
[(a b) (x y)]
[a b, x y]
{ foo: "bar" baz: "bak" quux: [a b c d] lol: 9.7E+42 }