I tried out the End-to-End encryption on Nextcloud. After reading the reviews on that plugin, I am glad it didn't work. People are loosing their data left and right with that thing.

Matt, the guy selling the kit is - presently - too specific in his offering.

He's not aware (as a taker of Lightning Btc) he has a responsibility to bypass corporate mandated robbery. Securing the global monetary network is far more lofty than any silly fee-collecting.