Choosing to delete an old and unused account is a great way to improve online security. Here's how to delete a Google Play Store account.
Google Playstore Configuration
How to Delete Your Google Play Account
Google Play Store: How to Sign Out / Log Off / Remove Account
Google to add 'data delete' option to Play store apps - Telecompaper
Google Will Require Android Developers to Make It Easier to Delete
How do I delete my app from Google Play?
Understanding Google Play's app account deletion requirements
Google Hopes To Make Play Store Users' Lives Easier With Simpler
How to delete your app from the stores?