A few notes.
HTML. Markup languages were in use within IBM to allow them to keep their huge volume of documentation up to date. IE The 1960's. Their use is briefly alluded to in The Mythical Man Month by Brookes. SGML (the parent to all modern standardized markup languages) was lead authored by Goldfarb of IBM. AFAIK these could be rendered on dumb terminals attached to S/360 mainframes.
Hyperlinks. IIRC Sir Tim was inspired by a Mac app from a company called "OWL" based in Wales. but I'm not sure anyone had the notion to generalize the link into something (potentially) linking across the whole web.
Rendering application. Or "browser." Well that idea has been around for since at least Smalltalk.
BTW the original VAX browser ran on the mainframe and wrote to (effectively) a frame buffer in main memory. It then invoked a (tricky) routine to compute the differences between it and the previous image to minimize the amount of bandwidth needed and speed up the rendering.
This is an old text editors trick.
TBL scores because he was in a place which needed vendor neutral systems (sure IBM, DEC or Sperry or Univac could probably sell you a terminal that would thrash a 1st generation web browser, at $50k/ desk :-( ) and he was smart enough to make it happen.
None of it was new, putting it together in a form that could be delivered right down to a dumb(ish) terminal was.
TCP/IP stack + HTML interpreter + rendering engine --> Browser.
Simple when it's laid out, is it not?
But that was then, this is now.
So let me set a little puzzle for the rest of you.
Take the bits of modern software infrastructure you're most familiar with and put them together (perhaps with some little tweaks) in a brand new way that 10s (100s?) of millions of people will use daily to solve a problem they did not realize they had.