I don't know if "killing off PAYG" is fair?
Yes, it is unfair, because it penalises extremely 'Light-users', especially when you consider the annual cost of maintenance, this is the ability to keep your number active, by making a chargeable activity every 180-days or 6 months as per the terms and conditions of most PAYG operators, before they cancel your SIM, delete your number with you forfeiting any unused credit.