The original vision for hypertext absolutely had multiple "browsers/clients" and feature parity between them was not even remotely an issue. The idea was that

The original vision for hypertext absolutely had multiple "browsers/clients" and feature parity between them was not even remotely an issue. The idea was that you tell the server what capabilities you have, it then tells you what it wants to offer you and a negotiation ensues. I have no idea where this concept of a "standardized hypertext client" came from! ;-)