I've confirmed that this worked in JobDSL 1.69 and stopped working in 1.70.
The functionality stopped having any effect on JobDSL generated PipelineJobs.
It is still possible to edit the job by hand and have this option enabled, but regenerating the job makes it disappear despite having "authenticationToken(xxxx)" in the script. What's worse, pipeline (ie Jenkinsfile) DSL does not permit setting this either, so there is no programmatic way of controlling this anymore.
It would be nice to know whether this is a regression or an intentional change - I've started coding around this (creating freestyleJobs to wrap the pipeline jobs just so they can be triggered remotely), but hopefully I don't need to.
Note: Migration claims that this functionality will be removed because Pipeline doesn't support it. Yet it appears to be already gone even though Pipeline does support it...