I appreciate your explanations, but you missed the obvious solution to many of the issues: *user selection*. Ok, some users "had concerns" with cloud file placement? Add a user selection, so we can move the file to the folder of our choice.
And for the love of all that is holy, why did you not simply add a compatibility mode to allow V6 users to continue using the former file format? I get it- the old format is "less secure". You know what? I DON'T CARE. I'd rather have a little less security and be able to use all of my devices than better security and only be able to use some of them. Now I can't use Enpass on my Windows Phones, so about half of my devices can no longer access my password management system. A compatibility mode would have let me use both V5 and V6 on my devices interchangeably until I phased out the older devices.
When MS Office switched formats in 2007, they left users with the ability to read and write both old or new formats TO THIS DAY, 12 years later, because they understand format changes aren't something you do overnight.
If you left a "V5 compatibility mode", half of the complaints here would disappear- desktop users could retain V5 and it's better UI/feature set, and those of us stuck with both versions could manage.