After a reply has been made in a topic, or even before maybe, a topic cannot be deleted by a regular user. Comments can usually edited or deleted, for a limited time.
You have that ability in deleting or editing the relevant comments, for a limited time.
Based on the category descriptions, the Lounge is the best category for The Philosopher's Kite
Moderators do have the technical ability to delete or hide topics. Since both topics have more authors than you alone, the topics should ideally not be deleted without the approval of the participants.
You could give arguments for and against hiding the topics. I’ll go along with your wish and hide the topics for now. Further discussion or insights may revert that.