Looks nice! And I don't want to always be that Emacs guy, but for anyone interested, you can (of course) have a similar setup, here's some packages:

https://github.com/rougier/nano-emacs (haven't tried, but clean look and defaults)

https://github.com/rnkn/olivetti (writing environment)

https://github.com/rnkn/fountain-mode (screenplay writing)

https://github.com/alphapapa/org-sidebar (sidebar)

https://github.com/jrblevin/markdown-mode (markdown, with preview too)

https://orgmode.org/ (of course, org-mode for everything)

https://github.com/junegunn/goyo.vim (distraction free mode)

https://github.com/reedes/vim-pencil (better behaviour for writing prose)

https://github.com/junegunn/limelight.vim (visual highlighting of current paragraph)

https://github.com/plasticboy/vim-markdown (better markdown syntax)

https://vim-voom.github.io/ (outliner sidebar)

Edit:

BTW, for my truly favourite aesthetic experience, I like to pair this setup with a nice dark theme, a high quality font, and cool-retro-term (https://github.com/Swordfish90/cool-retro-term/) emulating an old school CRT. Is this practical or ergonomic? Nope! But I love it!