ETH and Central Auth

Unlike BTC which truly has no ownership, Ethereum has CEO and company behind it which has the ability change the block chain from 1.0 to 2.0. this changes it from PoW or PoS.

This is a massive change to a block chain that promotes decentralised currency and contracts.

How is this truly be decentralised when such upgrades can happen?

If the rules can be changed at any point by the owners they are in fact no better then a government or bank.

Why should trust this central auth over my bank. I really want to have no central Auth. I don't want replace one for another.

Can someone clear this up for me? Just some thought floating around my head.

I am sure I am missing something.