Yes, I have been using it and really enjoying it for deploying web apps. So far I have deployed web apps using:
* fastapi (python)
* Django ninja (python)
* ghost cms (node)
I have been writing up my thoughts (and an example): https://andrewperkins.com.au/kamal/
The ability to deploy to both cloud servers and on-premises is a big win as I often work on projects that have a mix of both.
As the sibling comment says, it’s focussed on web servers. In my use case that is fine!