Depends on who you ask... LaTeX is a typesetting system that uses plain text commands to format and structure documents. Has a bit of a learning curve. It also (usually) does exactly what you ask it for.
Depends on what you wanna do. Also it's a matter of preferences.
For anything more complex than a simple letter or a table I'm using Latex. But although I love Latex, I must acknowledge that for some it's not the right tool.
It has advantages and disadvantages as everything in life ;) Ask your favorite search engine or LLM what those are, I don't feel qualified to elaborate on that.