My point was more that your categorical statement that "had both aircraft here been equipped with [ADS-B IN] then the outcome would have been different" should, I think, be tempered a bit with some qualifications: The equipment must be serviceable, the equipment must be configured to give alerts in these frequently low level and frequently close proximity helicopter operations and the pilots must be trained to know how the equipment works and not to ignore alerts.
My (inexpert) guess is that the number of alerts in those kinds of operations would quickly result in configuration selections to filter them out. That's why I look forward to seeing if the ATSB concludes that the much-hyped ADS-B IN functionality would have prevented this collision and terrible tragedy, and why.