I got a notification of a change on this ticket and reread the description.
This made me realize that the example is misleading in the same way the description text was: it's focused on the missing terminal operation, which is the scope of https://rules.sonarsource.com/java/RSPEC-3958, not of this rule.
I don't have an example to suggest, nothing obvious comes to my mind. Which leads me to wonder whether the difficulty of finding an example could be a smell of the rule being a bit fragile...