Wow you weren't around when the internet was being built.
So many topics here.
Let me just sum it up.

If another single company can turn off your app it is centralized.
At one point 100 percent of the ETH backbone was on AWS so they could have shut ETH done at any point.

AWS has global datacenters one power company or govenment wants to turn of accees. AWS does not go down.

This is the difference.
A lot of what you have brought up was heavily debated and solved when the internet was being built. Many things written on all those topics.

I am just trying to give you a high level macro view.