Donating to Wikileaks is entirely legal. The blockade undertaken by Visa and MC at the behest of the USG was extralegal; there were no charges against anyone at the time.
Even had there been charges, donating would still have been legal.
Furthermore, your criterion was “not better served”; please don’t move the goalposts.
Remittances and cross-border donations are way better served by cryptocurrencies than any other mechanism, full stop. It’s faster, cheaper, and way more reliable than any other method.
The fees come from fulfilling legal requirements like detection of money laundering and terrorism financing, and also customer security features like fraud detection and multi-factor authentication.
There are fintechs for customers who want lower fees and don't need e.g. physical branches or phone support. That's perfectly fine.
But a fintech that didn't perform KYC would be shut down pretty quickly by the police, so there's a floor on how low fees can be while remaining legal.