I'm closely involved with CFEngine (I work on CFEngine full-time); from what I see, CFEngine 2 market share is shrinking (though still quite large even though CFEngine 2 isn't "cool" and much talked about) and CFEngine 3 market share is growing (I help new users get started and there's been an uptick in demand for training).

Overall, CFEngine's share of the configuration management pie has shrunk compared to ten years ago but it's still a contender, especially in environments where low infrastructure footprint (CFEngine uses very little resources when it runs, and it is viable to use it on embedded devices - Internet of Things anybody?), scalability (5K hosts on one hub without breaking a sweat) and security (NVD shows a strong security track record for CFEngine: https://web.nvd.nist.gov/view/vuln/search) matter.

5k hosts is not that impressive, SaltStack can do that in dog slow CPython.