If your assets are still around, I think you will look into them immediately for verification. I have also used bitrex from 2016 and until now it is still intact, even though I no longer trade there, because I have withdrawn all the assets. In the last few weeks I opened a Bitrex account and there was a notification requiring me to re-declare the document, as I didn't have any assets there, so I released it.
In my opinion, this is possible to strengthen user security and to minimize theft.
KYc is not related with user security its just because of implemention from different regions and its all about to have all data about customers which is going to hurt very badly to this anonymous crypto world in next few years I am not going to use these exchanges and sites those asking for this all because I love my privacy and never want to share my all data with any shady site.