I think TeX doesn't take more than a "reasonable amount of effort" otherwise I, and many others, would use the alternatives.
And I'm interested where you got the "reasonable amount of effort thing" from. The TeXbook says nothing of the sort, for example:
"TeX, a new typesetting system intended for the creation
of beautiful books---and especially for books that contain a lot of mathematics."
Note the emphasis on the "beautiful" and "mathematics" rather than ease of use.
> I think TeX doesn't take more than a "reasonable amount of effort" otherwise I, and many others, would use the alternatives.
Sure. But most people who write documents don't use TeX. That might be because TeX seems to prefer using its own custom font system which doesn't work with any of their fonts, and lacks and modern GUI. TeX should have, and could have, been Word, with an emphasis on structure.
The projects goals came from its Wikipedia page, which admittedly isn't referenced.
Perhaps this misunderstanding of the goals for TeX is what makes your posts sound trollish. Most people who write documents don't need anything but the simplest of typesetting. The web is a collection of millions of documents, but it is built off about six fonts (of which only three get much use), using a very limited character set.
Most people who need good typesetting for technical documents use TeX, particularly if they want to typeset mathematical notation. Wikipedia requires minimal typesetting for the majority of its content, but the maths is set using TeX.
Why no TeX viewer? The goal for TeX was to typeset printed documents, books. PDFs work fine online, you could easily send someone a resume on paper or in a PDF, typeset using TeX.
Why no bundled TeX GUI? TeX didn't set out to be a text editor, it just handles typesetting for people who don't own printing presses. If it had tried to be a text editor, it would probably have been much less successful, and would be probably be forgotten by now.
Writing a WYSIWYG text editor is a very different challenge to writing a typesetting program. For example, TeX will try and lay out a paragraph so that there is no trailing single word on the last line. (And will produce warning messages if it can't find a way to make it look good.) To do that, you need to have access for the whole paragraph of text. However, in a WYSIWYG editor, as soon as the type hits the page, you want it to stay there. You don't want it moving about as you add text to the end of a paragraph, because it will feel like unpredictable, leading to a poor user experience.
Typesetting formulae graphically has similar problems, but they are even worse. The few GUIs for TeX that do exist are largely unremarkable, but notably they are GUIs which use TeX, it isn't a goal for TeX itself to provide one.
TeX's goal is beautifully typeset books, a goal it achieves.
(Specifically the typesetting of The Art of Computer Programming series of books, though obviously it is used in a much wider context.)
