Hi @AJ Khokra
Please see the similar post at https://community.spiceworks.com/topic/2278126-gpo-completely-disable-outlook-signatures
Deleting contents of Signature folder
https://community.spiceworks.com/topic/1960088-deleting-contents-of-signature-folder
How to prevent Outlook from adding signatures
https://www.codetwo.com/kb/how-to-disable-adding-signatures-created-in-outlook-for-exchange-users/
How to disable existing Microsoft Outlook signatures using a Group Policy Object
----------------------------------------
If this is helpful please accept answer.