Would have helped a lot of there would have been some sponsorship and adoption by banks, bigtech, governments. With only push from Snowden and a couple of nerds (I'm making a hyperbole :-) ) and it being complicated, inconvenient this never gained momentum.

Banks, bigtech, government choose other means, for their own reasons. Some of those might have been spies lobbying to hold on to their surveillance superpowers, for sure. Another might have been "not invented here".