• Q: Why is adding trailing commas allowed in all lists?
• A: Because it lets us write more robust and maintainable code, and has no known downsides.
• Q: But then why is omitting trailing semicolons not similarly allowed? Isn't it the same thing?
• A: No it's not. Just as those keywords "adding" vs "omitting" are opposites, so too the benefits of the first are the liabilities of the second.
• Two perspectives, subtly different