> The 1994 paper (freely available at https://digital.library.unt.edu/ark:/67531/metadc1341727/m2/...) is actually about proper E2EE.

That paper is about PKI-based session setup for End-End which is the ancestor of SSL/TLS. It even mentions a CAE which is effectively a CA and it does a synchronous handshake to establish a symmetric key. It's very clearly about transport layer security from end to end.

It's not about User-User E2EE (akin to Signal) and shares very little other than that data is encrypted from point A to point B.