You've just experienced how pathetically incompetent the people are who evaluated your request to update the Shopping API from 2 to 2.1 in the Apps Script code editor.
This is the standard behavior that happens on the Google Issue Tracker for Apps Script.
The level of stupidity exhibited from from the people working on Apps Script bugs is shocking.
I don't know if there is any hope for Apps Script in the future as far as providing the best capability.
Apps Script works fine for many uses, but it can't be relied upon if you want high quality, up to date capability.
It's still the best thing "out there" for lots of things.
But, the acceptable standard that Google has set for Apps Script is quite low.
I have no idea what the problem is on the Apps Script team.
I don't know if they are underfunded, or managed poorly, or are just a bunch of idiots.
But this level of incompetency from the Apps Script team gives me no confidence in them.
I've added my comment to the issue at: