Hi, BlockdCalls,
Thanks for visiting the Apple Support Communities. It sounds like you want to remove all currently blocked numbers from the blocked list, but do not want to do so individually. We are happy to provide you with some information.
Currently, deleting blocked numbers is done on a number-by-number basis: Block phone numbers, contacts, and emails on your iPhone, iPad, or iPod touch - Apple Support.
If you'd like to see an option to delete all blocked numbers at once in a later iOS version, you are welcome to let Apple know here: Feedback - iPhone - Apple.
Have a good day.