Greetings friends!

Cryptocurrencies are depicted as the decentralized currencies. Yes, they are decentralized in a sense that no one controls them and there is no system like central banks to control and regulate them. But, they are not true decentralized things as they are being presented.

Every crypto project is run by some company which controls many things. Bitcoin works on proof of work which needs immense resources to decode a code. Only big players can do so. They can purchase every such node and can have full authority over it. In platforms like steem and hive, who have the large stake, can do anything like downvoting others, destroying others' accounts and make policies which suits their interest. So, where is the decentralization? I can't find it anywhere. If I am wrong? Please correct me and explain why my thoughts are wrong.

Thank you!