"here are WYSIWYG editors for TeX as well." not there are not. Apart from TeXmacs I know of no editor which give you on the screen the same result you get on the paper. LyX has not such a feature. If an approximation is ok, then fine, but I do not think you can call it WYSIWYG. Is something else. And it requires a lot of work to do it correctly. You should at least appreciate the technical merits, even if you prefer to use LaTeX for its ecosystem. But as a user of both I see the clear merits of TeXmacs in terms of quality of my work (mathematician), I can focus more on what I'm doing, instead on deciphering the mess of the LaTeX formulas and try to find where to put a correction. I can give online lectures with it, discuss on zoom while scribbling on a TeXmacs document, much of the work I was doing on paper I do now directly on the computer. To me there is a clear difference in the user experience between TeXmacs and LaTeX and I will never go back to write LaTeX if I can help it (I do it sometimes, if my coauthors are using it and do not want to try otherwise).
As a fellow mathematician you may then appreciate the fact that local and global maxima may differ dramatically which pretty much precludes true WYSIWYG (not just in TeX) in that you have to settle for one of the two: visual output with suboptimal aesthetics (TeXmacs, and, to some extent, LyX) or perfect results that you have to compile with some delay. It has nothing to do with the computational power available but rather with the occasional highly unstable line breaking. Even in MS Word it is annoying sometimes to see it resize a current line even though it uses a rather lame line breaking routine. TeX does have facilities for almost real time WYSIWYG (SyncTeX was added specifically for that purpose) although they take some effort to set up. As far as concentrating on the work at hand I have written whole papers without compiling the document once before everything was complete. I admit it takes some getting used to but I prefer something I can grep through to a mere pretty picture. I admit if my work was heavy on large commutative diagrams I might have had a different view. One thing I totally agree with you on is that TeXmacs is an outstanding piece of software. I would just prefer to keep my documents in TeX (which TeXmacs can export, kinda).
> visual output with suboptimal aesthetics (TeXmacs, and, to some extent, LyX)
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)
From what I have seen in TeXmacs documentation, they have implemented pretty much every feature of TeX's linebreaking algorithm and more (microtypography, global page breaking, etc) so my claim above was not to say that the documents TeXmacs outputs have suboptimal aesthetics (to be fair, modern versions of TeX have all of these features, as well, although not the original TeX, alas). What I meant to say was there is no (even theoretically) possible way to have a perfect WYSIWYG editor if global paragraph/page breaking is desired. For example, due to global page breaking, one may be editing a line in the middle of the document and its position on the page (and the page number, left/right headers, etc) will be constantly changing---not good for the visual experience. I do not know how TeXmacs deals with these (extremely rare, admittedly) cases but the discussion was about the true WYSIWYG vs not so take it with a grain of salt. Let me say this again: TeXmacs is an outstanding piece of software. If in thirty years, a TeXmacs file format is still readable by the newest version (possibly with some easy tweaks), I will consider switching from TeX :). My other (minor) concern is that the LaTeX files that TeXmacs exports do not render at all as the pdf files TeXmacs produces itself. So as a WYSIWYG frontend to LaTeX, TeXmacs is ... not quite. Which they never claimed to be so I cannot fault them for this.
TeXmacs has its own macro language. The equivalent of \newcommand is \assign together with \macro (yes, TeXmacs has proper first class macros, like any respectable language, e.g. Lisp). And macros arguments can be edited visually, here's an example: https://twitter.com/gnu_texmacs/status/1251554336842407938
The phrase "it uses LaTeX" means that it runs the program LaTeX or that it need the "LaTeX format". Neither is true. Similarly you would say that "PanDoc uses Word?" or that a program that export to Word use Word. To me if you want to say that a program exports to a particular format just say so. If you want to say that a program needs a working installation of another program Y to work then you can say "it uses Y". So I think it is not correct to say that TeXmacs uses LaTeX. It can import/export it, like it can export/import PDF, HTML and other formats. TeXmacs does not need a working LateX installation to work. It comes with all its batteries included and on the Mac the app weight < 150 MB. That's all you need (including the LaTeX importer/exporter which is written in Scheme).
Part of the problem is that LaTeX is meant in multiple senses: there is the LaTeX installation along with all relevant programs, and then there is the LaTeX format/programming language. When I say I "use C", it means that I write C programs. In this sense, TeXmacs does use (the) LaTeX (programming language). It includes Scheme code which translates the internal TeXmacs format to LaTeX for obvious and extremely useful reasons. To me that means it uses LaTeX. YMMV.
I would really like to have names of packages you use regularly and you think you will miss in any other system. I can think only of TikZ, and again, for targeted purposes like DSL you can always ask TeXmacs to run LaTeX and get the output. See e.g. https://twitter.com/gnu_texmacs/status/1605167149173153793
Packages for chemistry are useful, even if I don't use them myself. Also siunitx needs yet a TeXmacs equivalent (I think https://github.com/pireddag/SIunits/tree/simple is not yet good enough)
You can just pick the AppImage if you like Linux. No installation needed. If you are on Mac, then you just need to give permission to run the software, it is not a specific problem of TeXmacs, it happens because TeXmacs executable are not signed. There are many reason you can turn down a software. any software. The point is: to whom are you making a favour? :) TeXmacs is free and make you save a lot of time. So I would say it is worth to spend a bit of it learning to use it properly. To be effective it require you to unlearn some LaTeX habits. But again, it is up to you. What I think is unfair is to deduce from these features that it is not a useful piece of software.
looking at some other comments in this thread and also to my experience, it not unnecessary clarification in the large. I'm glad you just were doing some humor. :)
