I don't actually spend much time in Obsidian yet, but its existence has enabled a major workflow shift.
Partly that's simply using markdown documents, and I was getting there anyway.
Mostly it's because it has made it easy to use WriteMonkey for nearly all of my writing (well, a lot is on Android but ends up in WriteMonkey; and Obsidian). I'll need to dig up the old workflow diagrams to look at the difference, though I'm not sure they'll reflect the extent of the experienced change.
Virtually everything can be in documents. All the fancy and bitty stuff goes into Obsidian. And WriteMonkey works on those parts that count as writing. The writing itself isn't the major part of writing - that's planning, researching, organising, revising, reviewing, editing, polishing, as well as everything related to publishing - but a comfortable environment for that makes a huge difference. Previously I wrote in a wide range of programs. Some of that was required, some was because I adapted easily, but mostly it was because the very different bitty needs of different projects pushed for
this program, then
that, and
the other. And there's none of that now.