All of their infrastructure from the very bottom to the very top is FOSS - except their membership program. It links to a third-party which processes payments compliantly.
They've attempted a pivot to funding the network via BTC/Lightning but clearly that's polarizing to a lot of people even though it better aligns with their philosophy.
I've been listening to the network for decades now and directly credit my IT career to the people who've been platformed on the various shows over the years. Lots of great content.