Unfortunately Aman, you and the developers have no idea how typesetters actually work. It is common to cut endnotes from a document and place them into another document. Yet still want to have the endnote references remain in the document you are cutting the endnotes from. When I look in the "Endnotes" document you referenced, the following is stated:
- Deleting entire endnote frame deletes all the corresponding endnote references.
It is absolutely absurd that Adobe would make this change to Indesign. You have effectively relegated typesetters to CC2017. Unless there is some sort of idiotic workaround to deal with your "improvement"?
I share your frustration!
Be sure to go vote for the feature request "Convert Endnotes to Static Text" on the InDesign feedback page. And add a comment to explain yourself too (there are 20+ comments on it to date). The engineers do read this page, quite closely, and often participate in discussions there.
Aman linked to the page already: Static Endnotes – Adobe InDesign Feedback