They can be trusted firms but the very first reason for the existence of bitcoin is to eliminate trusted third party aka custodians, fund managers, etc and by inheriting the same system for bitcoin too means we are just stuck with the same risks of being censored, controlled, rigged...

If you own bitcoin, you no need to trust anyone, just you have the complete access to your coins if you store them in a wallet that provide seeds/private keys and you are the ultimate controller of your funds, even if Satoshi wanted he can't do anything but that's not same with the way of ETF, or any custodial way of storing bitcoin.