This is a regression observed between Jenkins LTS 2.89.4 and LTS 2.107.2.

The version of the Job DSL plugin (1.69) is unchanged.

To reproduce:

1. Run the following Job DSL to create a folder and some sample views within that folder.

folder('/dir') {
  displayName('dir')
}
buildMonitorView('/dir/Test BMV') {
  jobs { regex('.*') }
}
listView('/dir/Test LV') {
  jobs { regex(".*") }
}

2. Run the following Job DSL script on its own.

folder('/dir') {
  displayName('dir')
}

Before the upgrade to Jenkins 2.107.2, this worked fine.  Following the upgrade, step 2 destroys the views that were created in step 1.