the most important part of this article now is the "Note of reflection" added 10 years after it's inception

Agreed; amazing to see this added. I suppose it's admirable... but the pain that has been inflicted on the teams I've been part of in the meantime... ugh.

I haven't seen it applied successfully in practice.

Neither.

I could see the value, in theory, for geographically separate teams spanning many time zones juggling concurrent development efforts. But the reality for a lot of commercial software development is totally the opposite. It's done in offices where staff are in at 9, out at 5, all working on the same features in a linear style. They're not developing an OS kernel; they're maintaining a CRUD app.

For that "git-flow", code needs to be in a state where it can have patches rebased/merged independent of one another. The codebases I've worked on have never been anywhere near that robust.