I started using LaTeX 11 years ago, and I used it for most of my academic writing (PhD thesis, manuscripts, conference presentations, etc.). At some point I also used RMarkdown for my slides and a few projects, with LaTeX as the engine. I loved the simplicity of Markdown, especially compared to LaTeX. It felt so much better to write # instead of \section{}. However, eventually, I went back to Microsoft Word and Microsoft PowerPoint.
I can think of a few reasons why I went ‘back to basics’. First, it was a requirement in my teaching that all slides were made available as PowerPoint files (PDFs were not allowed for accessibility reasons). And I believe most of the slides academics create with LaTeX are bad. Second, Word simply made it a lot easier to comment and collaborate on files (this is before Google Docs became great). Most of the people I work with use Word, and when English is not my mother tongue and I tend to write a lot of text, it made a lot of sense to rely on Word to pick up on typos and whatnot.
The other day I decided to give Quarto, the next-generation of RMarkdown, a change. I saw a few good examples of how it worked and as I was about to set up a new project from scratch, I thought I might as well give Quarto a chance. My initial assessment is that it is significantly better than RMarkdown and I can highly recommend that you check it out. In brief, Quarto is going to replace RMarkdown and if you are already used to RMarkdown, you should make the switch (try, for example, to simply run your .rmd file as a .qmd file in RStudio).
To get started, I can recommend Tom Mock’s webinar on Getting Started with Quarto (the material is also available on GitHub). There is also a very good guide for RStudio. Next, I recommend that you check out A Quarto tip a day and how to do parameterized reporting with Quarto.
Once you have the basics under control, you should check out a few productivity hacks for Quarto and then the forthcoming chapter on Quarto in R for Data Science. One of the things I really like about Quarto is the hashpipe (#|), and if you are already into RMarkdown, it will be very easy for you to make the transition.
You can also use it for webpages, see e.g., here, here, and here. I have no plans of using Quarto for any of my webpages, but it looks promising as well.
Last, you can find an overview of several Quarto resources here.