I suspect, that most of those users did not create such an elaborate setup, that has all those things. But perhaps, if there is a ready made config for all of it somewhere, maybe they are using that?
You don't really need an elaborate setup; it's sufficient to know how to install packages and explore some possibilities. It usually takes someone experienced to convince them that Emacs is truly the best choice for dealing with plain text. I'm not a musician, but I suppose if I was an aspiring and very talented guitar player and someone would convince me that Gibson Les Paul or Fender Statocaster is just the hands-down the best choice for the job - nothing would ever stop me from finding a way to have and use one, right?
And to leave you with a practical recommendation, not just philosophical rambling, here's https://github.com/pprevos/emacs-writing-studio. Note that I haven't used it myself. I don't know anything about it, beyond its existence.
