Isn’t $24k also a naive accounting of the annual cost of AWS in this case? What FTE-equivalent was required to set up the services they use at AWS? What FTE-equivalent is required to keep the annual bill down to $24k from say $48k or $100k?
I am curious why you think AWS services are more hands-off than a series of VPSs configured with Ansible and Terraform? Especially if you are under ISO 27001 and need to document upgrades anyway.
My point was that AWS is not hands-off. You still have to set it up, you have to keep a close eye on expenses, and Amazon holds your hand less than many people seem to expect.