I used it extensively in the late 90's early 00's and really liked it. As a newb sysadmin at the time, the built-in versioning on the fs saved me from more than one self-inflicted fsck up.
I can't imagine there would be any green-field deployments in the last 10 years or so - I'm guessing it's just supporting legacy environments.
This is not entirely the case.
I have been writing about VMS for years. The first x86-64 edition, version 9, was released in 2020:
https://www.theregister.com/2022/05/10/openvms_92/
Version 9.0 was essentially a test. 9.1 in 2021 was another test and v9.2 in 2022 was production-ready.
There's no new Itanium or Alpha hardware, and version 8.x runs on nothing else. Presumably v9.x is selling well enough to keep the company alive because it's been shipping new versions for a while now.
Totally new greenfield deployments? Probably few. But new installs of the new version, surely, yes, because VMS 9 doesn't run on any legacy kit, so these must be new deployments.
It's been growing for a few years. Maybe not growing much but a major new version and multiple point releases means somebody is buying it and deploying it. Never mind no new deployments in a decade... more new deployments in the last few years than in the previous decade.