Is there any OS that allows this config?

At least with Linux, if I encrypt my hard drive, I have to enter my encryption password on every login, for some even during boot.

Not sure about Windows. I wpuldn’t be surprised if you can have bitdefender on with auto login.

Mine autodecrypts with a hardcoded password in a text file. I don’t really care about encryption right now, but the minute I do, it’s one file delete away.