To be fair, if microsoft didnt automatically backup the keys, a simple BIOS/UEFI setting change, or windows update could trip the Secure Boot settings, which would clear all the TPM keys from the system, which means the sysyem would prompt you for the recovery key. I think people value being able retain access to their data over encryption. And to Microsoft’s credit, its not exactly a secret, they literally tell you that the key will be uploaded.