Not sure if you mentioned it, but cost and scaling is an absurd trick of AWS and others. AWS is literally 1000s, and in some usage cases even millions of times more expensive than your own hardware. Some believe that employee cost savings help here, but that's not even remotely close.
Scaling is absurd. You can buy one server worth $10k, that can handle the equivalent of thousands upon thousands of AWS instances' workload. You can buy far cheaper servers ($2k each), colo them yourself, have failover capability, and even have multi-datacentre redundancy, immensely cheaper than AWS. 1000 of times cheaper. All with more power than you'd ever, ever, ever scale at AWS.
All that engineering to scale, all that effort to containerize, all that reliance upon AWS and their support system.. unneeded. You can still run docker locally, or VMs, or just pound it out to raw hardware.
So on top of your "run it on bare metal" concept, there's the whole "why are you wasting time and spending money" for AWS, argument. It's so insanely expensive. I cannot repeat enough how insanely expensive AWS is. I cannot repeat enough how AWS scaling is a lie, when you don't NEED to scale using local hardware. You just have so much more power.
Now.. there is one caveat, and you touch on this. Skill. Expertise. As in, you have to actually not do Really Dumb Things, like write code that uses 1000s of times CPU to do the same task, or write DB queries or schema that eat up endless resources. But of course, if you do those things on your own hardware, in DEV, you can see them and fix.
If you do those in AWS, people just shrug, and pay immense sums of money and never figure it out.
I wonder, how many startups have failed due to AWS costs?
