It’s a lemmy account setting. If the Boost app does not expose the show “show scores” setting you can change it in a browser and Boost should reflect the change once you restart it. To make the change, just go to https://lemmy.world/ and go to your account settings after you log in.
You can’t keep secrets from the future.
Heard that once in a song about how all encryption is doomed to break against future math/computing power. Great eery phrase.