Many people say that they use LaTeX because it produces more beautiful output. Microtypography is one of the reasons for that. It's especially noticeable when microtype pushes hyphens or quotes at the end of a line slightly into the margin. (A nearby comment mentions that Typst has this feature, too.)
Nope, people don't need to know that something is done to appreciate the outcome. You might not know that modern MacBooks use ARM processors, but you might still appreciate that they have a long battery life.
Computer Modern is the very last thing I will ever want in a document and is the first thing I change in every LaTeX document I create. It is easily one of the ugliest fonts ever created.
It has a lot of good things going for it, but it is the least attractive font that I think I have ever seen.
I think it's quite attractive, but its attractiveness isn't really why it's desirable; it's because people know it is the font used by proper fancy scientific papers. It's like the opposite of Comic Sans.
How is that pdf made interactive? It has options to toggle the behaviour, which work even in an in browser pdf viewer. I did not think PDFs could do that.
PDFs can do a lot more than show static content. There was one time where Adobe strongly advocated for PDF to be the page format of what would come to be called "The World Wide Web". Where we have HTML now, Adobe wanted PDF. Thankfully that did not happen. But I suspect it would have made more sense technically than [whatever this mess is that we have now.]
That and Computer Modern. I bet a significant number of users use it because of that!
Personally I would just use LyX. Its equation editor is actually fantastic.