I think the issue with this formulation is what drives the cost at cloud providers isn't necessarily that their hardware is too expensive (which it is), but that they push you towards overcomplicated and inefficient architectures that cost too much to run.

A core at this are all the 'managed' services - if you have a server box, its in your financial interest to squeeze as much per out of it as possible. If you're using something like ECS or serverless, AWS gains nothing by optimizing the servers to make your code run faster - their hard work results in less billed infrastructure hours.

This 'microservices' push usually means that instead of having an on-server session where you can serve stuff from a temporary cache, all the data that persists between requests needs to be stored in a db somewhere, all the auth logic needs to re-check your credentials, and something needs to direct the traffic and load balance these endpoint, and all this stuff costs money.

I think if you have 4 Java boxes as servers with a redundant DB with read replicas on EC2, your infra is so efficient and cheap that even paying 4x for it rather than going for colocation is well worth it because of the QoL and QoS.

These crazy AWS bills usually come from using every service under the sun.