The main thesis seems to be that the user should be able to press View Source and understand what's going on. I agree, at least for web
sites. For web
apps, at least anything over 50 lines, you are probably going to want to use a typed language. (Well, you could technically use .js with TypeScript compiler and type annotations in special comments but I did not find that very pleasant.)
I used to be really big on this, though (and it makes me sad that these days most sites are 1 big unreadable line of HTML). In fact, I find a beauty and elegance in shipping the whole thing as a single HTML file with no dependencies (1 network request!), though I did eventually make a "build system" (my build system is cat) so I could have a sane editing experience. Boom, self-contained portable software in 1 human-readable file!
Along the same lines, I think the coolest thing about web development is that you can make your first (interactive!) programs with Notepad and whatever browser ships with your machine. (Just drag the HTML file onto the browser!) It's magic!
Edit: Just found an unexpected benefit of self-contained HTML: makes your software immune to bit rot. I tried loading an old project of mine on Web Archive but it hadn't archived the external JS file! Sad! Meanwhile, this one loads fine because all the JS is in the HTML! Winning!
https://web.archive.org/web/20210508133239id_/https://andai....
This is my homage to the old SodaPlay Constructor. (Never made an editor, sorry!) Feel free to view-source!