None of them have become the standard. But some of the ones above - though excluding Markdown - are a complete replacement.
Actually, even Markdown stands a chance if supplemented with enough HTML and CSS. HTML and CSS have practically replaced most non-maths uses of Latex.
HTML and CSS basically do a lot more than Latex does - except for maths things - and are far more widely known, and far more forgiving. Also importantly, they support hyperlinks, animations, and inline interactive scripts. It seems that HTML and CSS with the appropriate CSS styles and shorthands (like Markdown) could eat up everything that Latex does and much more. I don't know if Latex can survive the onslaught.
1. You mentioned forgiving. One may not like the style of TeX error messages but its tracing facilities are extensive and given enough time and perseverance one can track nearly any layout issue down an correct it. Compare this to CSS silently ignoring incorrect syntax, having different syntax across browsers, etc. I would take strict syntax checking over this mess any day.
2. Many complained that LaTeX has more than one way of achieving the same result. True but how many ways are there of centering a div on a page? I can list six off the top of my head and there are probably more.
3. You casually mentioned '...except for maths things...' but this is far from minor. I cringe when I read engineering papers not written in TeX: the formulas are so ugly that they border on unreadable.
4. CSS may be wider known but unlike TeX CSS is a moving target. Being designed by a committee it carries all the flaws, like kludgy design in the name of 'compatibility', poor choices of syntax to make it appeal to a wider audience, etc. The designers of CSS are so enamored with the 'cascade' but in practice it is rarely used as intended. The 'important!' kludge as a perfect testament to this.
5. LaTeX syntax may be unappealing to some but HTML takes it to a whole other level: whitespace that affects the layout yet no easy way of getting rid of it (HTML style comments are a torture device); too verbose... one may not like the backslash but what about <...> </...> ? Five extra symbols!
6. LaTeX engines produce full featured PDF so hyperlinks are not a problem (most LaTeX documents have them). Yes, CSS has so called 3D graphics but it is anything but programmer friendly. What good are 3D transforms if one cannot even use simple lighting effects programmatically; c'mon, at least give me Lambert reflection! Incidentally, inline JavaScript can be included in pdf documents produced by LateX as well (although ... why?)
LaTeX’s usage has only increased with the creation and growth of the web. What makes you think it’s going anywhere?
People are write something like Kotlin html dsl
> HTML and CSS have practically replaced most non-maths uses of Latex.
Huh? You must be totally ignorant of the uses of LaTeX.
First of all, this:
> None of those are a complete replacement, except maybe Lyx, and it’s based on LaTeX.
Source: Your [censored].
> Huh? You must be totally ignorant of the uses of LaTeX.
Outside of academic papers and books, what?
But what does it tell you that such an ugliness remains and the way to fix it is relatively unknown? It surely can't be a pro-TeX tell!
Till now I took the developers word that the aesthetics of TeXmacs is better than the one of TeX and I would be curious to know where the opposite is true (and in case also why this cannot change)