At $0.045/hour, NAT gateways are expensive. This sets up perverse incentives, as it's cheaper to keep wasting public IPv4 addresses. If anyone from AWS is watching, I suggest that you make the base fixed price of NAT gateways way cheaper, and maybe add a small extra charge for EC2 instances and Fargate tasks with public IPs.
You need one of those per AZ, and multiples of that if you split up projects across VPCs or AWS accounts.
AWS accounts and VPCs are free, so NAT gateways can form a significant part of the per-account/VPC base cost, which can be a significant part of your total cost for a small project/environment.
