It's good they did the math. AWS doesn't fit everything. Really, the main things that cost actual money in AWS are memory and CPU (that's including elasticache

It's good they did the math. AWS doesn't fit everything. Really, the main things that cost actual money in AWS are memory and CPU (that's including elasticache, RDS, etc). Bandwidth can be negotiated away. I'm sure you could do some kind of super deal on CPU/RAM, but we've never bothered. Would it be worth it to rearchitect your app so it doesn't use 2TB of RAM? Probably not. You have a lot of sunk costs, and redoing everything will probably break everything. You guys are big enough that CapEx doesn't matter that much. You just need big boxes with lots of bandwidth. If you're happy with what you've got, stay with it.