Not all cryptocurrencies are scams, not all traffic on Tor is CSAM, and not matrix messages are spam. Some of us use all of these decentralized systems daily for their actual intended use cases of sovereignty and privacy.
Things like money and messaging are too important to a functioning society to allow any single party to control.
We need -actually- decentralized money and -actually- decentralized communication.
MobileCoin and Signal are neither and the results are predictable.
That's why there is no single party to control communication, and even for money there is US vs EU systems.
"Actually decentralized" has a lot of problems, especially with things like spam and scams (see also: usenet). Federation makes sure no single party has too much power, and yet allows one to have usable systems.
Well I have clients that pay me in cryptocurrencies monthly, and I pay for goods and services with them regularly without Visa or Mastercard learning my purchasing behavior to sell to advertisers.
Sure cryptocurrency is not as widely accepted online or in person locally as US dollars, but it is far easier to spend those same places than my Euros which actually meets your definition of money.
A medium that can be exchanged for goods and services and is used as a measure of their values on the market, including among its forms a commodity such as gold, an officially issued coin or note, or a deposit in a checking account or other readily liquefiable account.
Things like money and messaging are too important to a functioning society to allow any single party to control.
We need -actually- decentralized money and -actually- decentralized communication.
MobileCoin and Signal are neither and the results are predictable.