It's something on the radar for sure

Is there something specific that isn't working for this right now?

Last time I checked it wasn't possible to define "FTP Servers" configuration over JCASC using yaml files.

Any news on this?

Here you have a screenshot of the problem. There is no way to define any configuration over the yml file.

I made a groovy script as workaround which is executed with the configuration-as-code-groovy-plugin: https://gist.github.com/jeykey/e6eec8974c111b43bd39d79b31074db1
Not very clean but it does the job. 
This overwrites all existing server configurations! You also might want to implement some secret handling for the password.

For your information, all publish-over-ftp component type JENKINS issues related to the Publish Over FTP plugin have been transferred to Github: https://github.com/jenkinsci/publish-over-ftp-plugin/issues

Here is the direct link to this issue in Github: https://github.com/jenkinsci/publish-over-ftp-plugin/issues/68
And here is the link to a search for related issues: https://github.com/jenkinsci/publish-over-ftp-plugin/issues?q=%22JENKINS-54780%22

(Note: this is an automated bulk comment)

This issue has now been marked as Closed - Postponed. Please see the corresponding Github Issue if you need to follow up on it.