It’s a rant, for sure

first of all, bitcoin in its original form was meant to be used as a transaction log between banks.

Satoshi Nakamoto, they guy who invented Bitcoin, was motivated by a desire to circumvent banks. Bitcoin is the exact opposite of what you claim:

A purely peer-to-peer version of electronic cash would allow online payments to be sent directly from one party to another without going through a financial institution. … Commerce on the Internet has come to rely almost exclusively on financial institutions serving as trusted third parties to process electronic payments. … What is needed is an electronic payment system based on cryptographic proof instead of trust, allowing any two willing parties to transact directly with each other without the need for a trusted third party.

https://www.bitcoin.com/satoshi-archive/whitepaper/

My comment is a rant, because I constantly see these strongly held opinions about systems by people who not only know nothing about the topic, but who believe utterly false things.

cryptocurrencies result in a centralisation of power by default, whether they use proof of work or proof of stake, because they are built so that people with more resources outside the network can more easily get sway over the system

Ok, now I have to wonder if you’re just trolling.

Bitcoin, in particular, has proven to be resilient against such takeovers. They’ve been attempted in the past several times, and successfully resisted.