I’ve been saying for a couple of years whoever builds a tool to one click deploy an AWS alike to run on local bare metal has built the next billion dollar a year company. I know of a lot of big shops that are desperate to get out of the cloud due to 7-8 figure AWS bills but their software and engineering is too tightly wound into AWS tooling.
But AWS is huge. They employ thousands of engineers. Granted most of the complexity is due to its huge huge scale, but still it has too many features to do what youre asking. And then there are AWS exclusives like DynamoDB. Yes there are open source public/private cloud alternatives like OpenStack but they won't solve the problem of lock in and you'd still have to change all your tooling.
Conflating lock in to an open source tool with lock in to a vendor who you literally have to keep paying money to survive is a shitty tactic used by companies like Amazon.
Using open stack absolutely solves the problem of lock in from a business perspective. You can’t be cancelled, the price can’t be changed, etc.