Shame it was such a poorly researched report though.
I believe properly adjusted and clean HIDs can be really good to see by. Dirty, poorly adjusted ones are awful for other road users, but that said, so are dirty or poorly adjusted standard headlamps. HIDs fitted as OE have proper automatic level control, and headlamp washers. There are unfortunately many kits around to convert standard headlamps to HID (High Intensity Discharge), and these don't have those safeguards as standard.
That doesn't mean that retrofit HIDs are automatically bad, just that the chance of them being a problem is higher. The report touched on this, but largely glossed those issues.