I have such a love-hate relationship with Latex.
I use it almost every day.
I love how easy it is to write beautiful math, and how easy it is to organize well large documents. It's fast (in general).
And, thank god, there are lots of information online.
But boy do I hate the whole semi-broken macro-based system.
The package management feels so outdated.
Errors are hard to decipher. Package documentation is there but takes days and days if you actually want to read it.
And then you use Tikz. Same result. Beautiful neat graphs. Horrible obscure macro based system with impossible-to-understand error messages.
Gosh yeah. Imagine writing a 150+ pages thesis in Word. Would give me nightmares.
EDIT: To complement: I think it's obviously possible, lots of people do it. But I feel I would spend a lot of time on "keeping the structure right" as I edit it. Feels more straightforward with Latex. And then Math is kind of hard to write efficiently, but that's field specific.
I only needed a single dose of 'Word has decided to move every single image, table and textbox all on top of each other at the very beginning of the document for no apparent reason' before I vowed never to use Word for anything important or complicated.
I wonder about that. I don't know word well enough at all to accomplish the same things I do in latex. But I know it can do a lot of those things.
I assume it would be similar if I knew as much about word as I do about latex. But there's no way of knowing, as I am not going to learn word without a much better reason than "i wonder if it's actually terrible to write 150 pages when you know how to use it."
While Word has evolved to do many of the things that were exclusive to LaTeX at one point, the problem is that Word is not extensible. When you hit a wall in Word, that’s it — you have no options. In LaTeX you can pretty much always figure out how to do what you want to do, even if it takes learning a fair bit about the packages, and if you don’t want to spend that kind of time you can almost always find relevant info on stackoverflow.
Either that changed, or you are technically incorrect. Word is heavily extensible through OLE. You can probably even embed a live ConvNet or a 3D physical simulation in a document. Hell, that was mentioned in Windows 95 book I read as a kid. They used to call it "multimedia".
Start by splitting it up into parts, each document not to contain more than 5-10 pages, then enable "limit formatting to a selection of styles" (anyone who disables this is to suffer the ordeal of the boats). Once everything is the way you want it, copy everything to a new place, add a master document and set the styles as you want. The export to PDF, publish or whatever you want.
If you want it truly beautiful, use a DTP and don't format the word documents at all.
I've done a 70 pages proposal on a computer vision study on Word once (plenty of images). I don't have nightmares with it anymore because I'll never open it again, and never make that stupid decision again (Even if the other side requires it!).
I've edited some ~100 pages regulations (so very few pictures and tables) on Word files too. It's not a nightmare because Open Office works quite well with those.
The main advantage of LaTeX is that the format is more-or-less transparent. I say "more or less" because last time I claimed it is transparent, someone showed me their .tex files and sure I could not understand them, but by now this has been the only time I could not understand a .tex file (this was someone who used macros to decline nouns, among other things; it's not a common use case).
In general, if you see a .tex and cannot compile it, you can look inside and get a good idea of what the file is about in 5 minutes; a bit more time and you can essentially read it by hand. I don't know of any other semi-popular text format except well-written html+css (which is insufficient for science) that supports this. The cleanest systems will go obsolete and become unsupported; if I want my writings to stay around for 200 years, my best bet is to write them in a format that does not strictly require any decoder. And LaTeX, as commonly practiced, is such a format.
There are other TeX dialects, too. AMSTeX bid to become its own dialect, for a while, but I think what's mainly happened is that people who want its functionalities use them as a package (or packages) on top of LaTeX. ConTeXt is the big non-LaTeX dialect of which I'm aware.
I feel similar about latex. I love how easily I can write math in it, how neat the result looks and how I can structure larger documents easily.
But I hate the syntax, that seemingly simple tasks have arcane syntax or are hard to acomplish and mostly, that it's damn slow to compile. I was really surprised that you consider it fast, it's really interesting to me!
There are LaTeX distros, but just a few of them. Most people on linux use the TeXLive distro. I recently downloaded the latest version from its home (https://www.tug.org/texlive/), and I think it took something like 6GB on my disk. Probably half of that is font files. TeXLive is in (for example) the Ubuntu repositories, but they are usually way behind the release version. I’ve heard there is a distribution for Windows, and probably for MacOS.
The most common windows version is probably miktex which comes with its own package manager which by default downloads packages on use, while texlive often is most easily used in the full scheme installing every package, but there exists a separate package manager as well, which is often not included as distros want you to use the OS package manager.
But boy do I hate the whole semi-broken macro-based system. The package management feels so outdated. Errors are hard to decipher. Package documentation is there but takes days and days if you actually want to read it.
And then you use Tikz. Same result. Beautiful neat graphs. Horrible obscure macro based system with impossible-to-understand error messages.