The Google Slides app is compatible with my Android TV -
https://play.google.com/store/apps/details?id=com.google.android.apps.docs.editors.slides&hl=en_GB

From memory I believe I can install apps without a password. I believe even changing Google Play to require authentication for purchases will not enforce this for free applications.

So yes - it is possible to access google data via applications.

If this is not desirable then you either need to use a different Google account or use something like [AppLock](https://play.google.com/store/apps/details?id=com.domobile.applock&hl=en_GB) to restrict access to Google Play and any other applications with permissions you aren't happy sharing with other TV users.