I've worked in an environment where they used git-flow, but it was very much a "traditional" (?) software company; they offered long term support, that is, backporting patches to older released versions, that kinda thing.

But they also had long lived branches that lived for like 9 months. It was still manageable because the feature was usually limited to one 'domain', and they usually had only one or two people working on the feature at once.