The problem is that Microsoft gives users a false sense of security. Marketing speak for this feature is "Your device is always automatically encrypted", which results in users thinking their data is safe. The content is then automatically backed up to Microsoft servers, to which users will not have much of an objection since it's encrypted anyway. But then behind their backs, Microsoft not only stores the encryption keys as a backup but also immediately shares them with the NSA that has full access to those backups.

So basically they fucked up three times: 1. Marketing encryption while it's not safe, 2. Storing accessible backups of your data on their servers and 3. Actively sharing those backups with the NSA.

Out of those, #1 would be an excusable thing that many companies do, #2 is a reason to mistrust them and #3 is a reason never to store anything with Microsoft ever again. It's just not acceptable to take my data, promise me it is encrypted, then lie about it and freely share my data with the NSA whenever they want.