This site uses nginx in directory mode, with fancyindex.

https://github.com/aperezdc/ngx-fancyindex

Http isn't going to dissapear overnight and other protocols require
other browsers that most people don't have,  but it is possible  to 
make lightweight sites where content is king. 
The smolweb initiative is working  towards  this  goal.  Here  I've 
taken another path,  to use the web server as a file sharing server 
in directory mode, where html is just one file format among others.

GUI BROWSERS ------------------------------------------------------

If you are using Firefox or a deriative the extensions linkificator
and content-type fixer could come in handy.

https://addons.mozilla.org/en-US/firefox/addon/linkificator/

https://addons.mozilla.org/en-US/firefox/addon/content-type-fixer/

The font sizes depend entirely on your browser settings. 
For example, on my 1366x768 96dpi screen in Librewolf I have the 
following:

Proportionel: Serif , Size 14
Serif: Liberation Serif
Sans-Serif: Liberation Sans
Monospace: Liberation Mono, Size 18

TEXT BROWSERS -----------------------------------------------------

You can also use it with any text mode web browser, Lynx, W3M, etc.
My personal preference goes to Chawan:

https://sr.ht/~bptato/chawan/

If you are using the Chawan text browser you'll find it just works. 
Also Chawan is multiprotocol, so you can access gopher, gemini ftp, 
spartan, etc. links within the same browser. Hit ":" and  the  text
files become linkified.